Answer:
The correct answer is B
Explanation:
This question seeks to test the difference between mass and weight.
Mass is a measurement of the amount of matter present in an object. While weight is a measurement of the force of gravity pulling (the mass of) an object. Hence, measuring the weight of the moon rocks in the moon might be a waste since the weight of the object on earth will produce a different value due to the difference in the force of gravity between the earth and the moon.
Answer:
b
Explanation:
-K-12 Scientific Method
3/10
A(n)
simply states what will be observed and always
true, but does not explain why.
Answer:
The correct answer is - scientific law.
Explanation:
A scientific law is an explanation to a well observed phenomenon of the world which is found true every time tested and universal proven fact, but the reason behind the phenomenon and its existence.
To explain the scientific law there will be various explanation that are called scientific theory, however these theories can not be proved.
Thus, the correct answer is - scientific law.
Why is particle size the main parameter used in selecting a mechanical phase-separation device?
Answer:
This is because mechanical phase-separation device such as filtration, centrifugation etc operate according to the unique particle size feature in which they are designed to separates.
The process of centrifugation separates particles of size range between 0.1 μm to 5.0 μm efficiently.
The process of filtration however varies as there are different types of pore sizes which covers a wide range of particle sizes.
5 (01.01 LC)
Which of the following would be a warning sign that information about a weight loss medication is not reliable science?
Answer:
The scientists and all test subjects involved in the investigation work for the company that sells the medication.
Explanation:
The options are as below:
A. The investigation compared a group that took the medication to a control group that did not take the medication.
B. The scientists and all test subjects involved in the investigation work for the company that sells the medication.
C. The weight loss medication worked for 95 out of the 100 test subjects, while only 15 of the 100 control subjects lost weight.
D. The weight loss results were replicated by scientists conducting a study at an independent institution
The correct option would be that the scientists and all test subjects involved in the investigation work for the company that sells the medication.
When selecting the test subjects for research, the selection must be as random as possible so as to ensure an unbiased outcome and increase the reliability of the research.
Limiting the test subjects to those that work in the company that sells the medication will generally reduce the reliability of the outcome because of element of bias that can be introduced either knowingly or unknowingly.
The test subjects must have been selected from the general population of target users for the medication and not limited to just the employees of the manufacturing company.
Correct option: B
Which of the following is NOT a product of the electrolysis of NaCl? A. Chlorine gas B. None of these C. Hydrogen gas D. Oxygen gas
Answer:D. Oxygen gas
Explanation: because the experiment showed
A botanist measures a plant growth at 3cm over a two week period. The information she gathers is called.
Answer:
The correct answer is quantitative data.
Explanation:
The value of data in the form of numbers of counts where each set of data exhibits a specific numerical value associated with it is termed as quantitative data. This information refers to any quantifiable knowledge, which can be used for statistical analysis and mathematical calculations so that decisions of real-life can be taken based on the mathematical outcomes. The quantitative data is used to find the solutions of the queries like how often, how much, or how many.
In the given case, a botanist measured the growth of the plant for two weeks, and the outcome came in the form of numerical value. Thus, the knowledge she collected is known as quantitative data.
Scientific method quick check
Answer:
Quick you said:
-Purpose/Question
Ask a question.
-Research
Conduct background research. Write down your sources so you can cite your references. In the modern era, a lot of your research may be conducted online. Scroll to the bottom of articles to check the references. Even if you can't access the full text of a published article, you can usually view the abstract to see the summary of other experiments. Interview experts on a topic. The more you know about a subject, the easier it will be to conduct your investigation.
-Hypothesis
Propose a hypothesis. This is a sort of educated guess about what you expect. It is a statement used to predict the outcome of an experiment. Usually, a hypothesis is written in terms of cause and effect. Alternatively, it may describe the relationship between two phenomena. One type of hypothesis is the null hypothesis or the no-difference hypothesis. This is an easy type of hypothesis to test because it assumes changing a variable will have no effect on the outcome. In reality, you probably expect a change but rejecting a hypothesis may be more useful than accepting one.
-Experiment
Design and perform an experiment to test your hypothesis. An experiment has an independent and dependent variable. You change or control the independent variable and record the effect it has on the dependent variable. It's important to change only one variable for an experiment rather than try to combine the effects of variables in an experiment. For example, if you want to test the effects of light intensity and fertilizer concentration on the growth rate of a plant, you're really looking at two separate experiments.
-Data/Analysis
Record observations and analyze the meaning of the data. Often, you'll prepare a table or graph of the data. Don't throw out data points you think are bad or that don't support your predictions. Some of the most incredible discoveries in science were made because the data looked wrong! Once you have the data, you may need to perform a mathematical analysis to support or refute your hypothesis.
-Conclusion
Conclude whether to accept or reject your hypothesis. There is no right or wrong outcome to an experiment, so either result is fine. Accepting a hypothesis does not necessarily mean it's correct! Sometimes repeating an experiment may give a different result. In other cases, a hypothesis may predict an outcome, yet you might draw an incorrect conclusion. Communicate your results. The results may be compiled into a lab report or formally submitted as a paper. Whether you accept or reject the hypothesis, you likely learned something about the subject and may wish to revise the original hypothesis or form a new one for a future experiment.
What is an empirical formula?
Answer:
a formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.
Hope this helped!!!
Answer:
Empirical formulas show the simplest whole-number ratio of atoms in a compound
Explanation:
A student is worried about determining if a chemical is radioactive. Which
section of the SDS would the student refer to?
Product Information
Fire Fighting Methods
Physical and Chemical Properties
Hazards Identification
Answer:
Hazards Identification
Explanation:
A safety data sheet, SDS, is an informational document provided by the manufacturer or importer of a hazardous chemical detailing the chemical, physical, health, and environmental health hazards associated with the chemical as well as safety precautions in handling the chemical.
Some of the sections in the SDS include:
Product Information: It identifies the chemical as well as its recommended uses. The contact information of the manufacturer is also provided.
Fire fighting methods: It gives measures and guidelines necessary for fighting a fire caused by the chemical.
Physical and chemical properties: states the physical and chemical properties of the chemical substance such as: appearance, odor, pH, melting/freezing point, boiling point and boiling range, flammability, etc.
Hazards identification: states the hazards of the chemical and the necessary warnings regarding the hazards. Some of the information provided include: hazard classification of the chemical (for example flammable liquid, oxidizing gases,explosives, etc), signal word, hazard statement (for example radioactive), pictograms, precautionary statements, etc.
From the above information provided, the student should refer to the hazards identification section.
why is carbon iv oxide used in fire extinguishers
Answer:
Carbon dioxide extinguishes work by displacing oxygen, or taking away the oxygen element of the fire triangle. The carbon dioxide is also very cold as it comes out of the extinguisher, so it cools the fuel as well.
Compound A, C6H12O2, was found to be optically active, and it was slowly oxidized to an optically active carboxylic acid B, C6H12O3, by Ag(NH3)2. Oxidation of A by anhydrous CrO3 gave an optically inactive compound D that reacted with Zn amalgam/HCl to give 3-methylpentane. With aqueous H2CrO4, compound A was oxidized to an optically inactive dicarboxylic acid C, C6H10O4. Give structures for compounds A, B, and C; do not specify stereochemistry.
Answer:
kindly check the attach file for the drawing of the chemical structures.
Explanation:
So, we are going to start from the compound D, which is stated in the question to be optically active. Therefore, we will have that:
STEP ONE: THE OXIDATION OF COMPOUND A, C6H12O2 TO GIVE COMPOUND C.
The oxidation of compound A,C6H12O2 gives another chemical compound that is chemical compound C which is a optical inactive di-carboxylic acid. The chemical equation is given below:
C6H12O2 + H2Cr2O4 --------------------------------------------> HOOCCH2CHCH3CH2COOH.
STEP TWO: THE OXIDATION OF COMPOUND A, C6H12O2 TO GIVE COMPOUND B.
The oxidation of compound A,C6H12O2 gives another chemical compound that is chemical compound C which is a optically active acid. The chemical equation is given below:
C6H12O2 + Ag(NH3)2^+ -----------------------------> C6H12O3.
Since the question asked us to give the structures of Compound A,B and C there is no need to to show the chemical reaction for compound D.
Kindly check the picture below for the chemical structures.
Describe the reaction of an acid with an alkali.?
Your question has been heard loud and clear.
The reaction of an acid with an alkali is neutralization reaction. It is a neutralization reaction because , they both neutralize each other (means it makes them chemically inactive after reacting) and produce a salt , and maybe water too.
An example: hydrochloric acid + sodium hydroxide → sodium chloride + water
Thank you
it will neutralise because if you add both of them together with a matching Ph such as 5 and 9 equally then it will neutralise and have a Ph of 7
could you please make me brainliest
explain how sodium and calcium react with water. explain with equations
Reaction of sodium with water
Sodium metal reacts rapidly with water to form a colourless solution of sodium hydroxide (NaOH) and hydrogen gas (H2). The resulting solution is basic because of the dissolved hydroxide. The reaction is exothermic. During the reaction, the sodium metal may well become so hot that it catches fire and burns with a characteristic orange colour. The reaction is slower than that of potassium (immediately below sodium in the periodic table), but faster than that of lithium (immediately above sodium in the periodic table).
2Na(s) + 2H2O → 2NaOH(aq) + H2(g)
Calculate the pressure drop over a 100m length due to friction when a slurry made from 1.0-mm silica particles is pumped through a horizontal 6-cm diameter pipeline (smooth pipe) at 2.5 m/s. The slurry contains 25 per cent silica by volume. The density of silica is 2700 kg/m3, rhow = 1000 kg/m3, μw = 0.001 kg/ms. Use a value of 82 for Ω. Drag coefficient for these particles,CD, may be taken as 0.44 .
For the slurry/Pipe system in question 1, estimate the deposition velocity.
Answer:
The answer is "2.78".
Explanation:
Given values:
CD= 0.44
Formula:
[tex]\bold{f_r= \frac{v^{2}}{ g(s-1)D}}[/tex]
g=9.8
s= 2.7
D= 0.06
[tex]\to f_r=\frac{2.5^2}{9.8(2.7-1)0.06}\\\\[/tex]
[tex]=\frac{2.5 \times 2.5}{9.8 \times 1.7 \times 0.06 }\\\\=\frac{6.25}{.9996 }\\\\=6.252501[/tex]
[tex]\phi = \frac{82\times v}{ \sqrt{cD} \times f_r^{-1.5}}\\\\[/tex]
[tex]= \frac{82 \times 0.25 }{ \sqrt{0.44} \times 6.25^{1.5}}\\\\=2.4285\\[/tex]
[tex]\frac{\bigtriangleup P f_1 s_1}{L} = \frac{\bigtriangleup Pf_w}{L}(1+\phi)\\[/tex]
[tex]=\frac{2fwSwv^2 (1+2.4285)}{D}\\\\[/tex]
[tex]Re= \frac{D \bar v Sw}{M_w}\\[/tex]
[tex]=\frac{0.06 \times 2.5 \times 1000 }{0.001}\\\\=\frac{150 }{0.001}\\\\= 150 \times 10^{3}\\\\= 1.50 \times 10^{5}\\\\[/tex]
[tex]fw= 0.00389[/tex]
[tex]\to \frac{\bigtriangleup P f_1 s_1}{L}[/tex]
[tex]\to \frac{2 \times 0.00389 \times 1000 \times2.5^2 \times 3.4265}{0.06}\\\\\to 2.78[/tex]
begging u to answer Which is not an inter molecular force? Select one: a. Inter atomic bonds b. van der waals forces c. hydrogen bonds
Answer:
a-Interatomic bonds
Explanation:
First of all, it is not a force. Let alone be molecular force.
Suppose a compound is involved in three different reactions denoted R1, R2, and R3. Tripling the concentration of this reactant in all three reactions causes the rates of reaction to increase by factors of 3, 9, and 1, respectively. What is the order of each reaction with respect to this reactant? 1. R1 = 1; R2 = 2; R3 = 0
Answer:
The order of reaction is as follows, R1 = 1; R2 = 2; R3 = 0
Explanation:
The rate of a chemical reaction is the number of moles of reactants consumed per unit time or the number of moles of products formed per unit. the rate of a chemical reaction is affected by the concentration of reactants
The relationship between the rate of a chemical reaction and the concentration of its reactants is given by the rate law or equation.
Generally, the rate equation is given as;
Rate = k[A]ᵃ[B]ᵇ..., where k = rate constant which is independent of concentration of the reactants, [A] = concentration of reactant A, a = order of reaction A, [B] = concentration of reaction B, b = order of reaction B.
For the given reactions R1, R2 and R3
For R1; rate = 3, Concentration = 3[A]
3 = k[A]3ˣ
3¹ = k[A]3ˣ
Since rate is proportional to concentration, therefore, the order of reaction, x = 1
For R2; rate = 9, Concentration = 3[A]
9 = k[A]3ˣ
3² = k[A]3ˣ
Since rate is proportional to concentration, therefore, the order of reaction, x = 2
For R1; rate = 1, Concentration = 3[A]
1 = k[A]3ˣ
3⁰ = k[A]3ˣ
Since rate is proportional to concentration, therefore, the order of reaction, x = 0
Therefore, the order of reaction is as follows, R1 = 1; R2 = 2; R3 = 0
6th edition before we begin, let's first establish an understanding of basic terminology. it may be harder than you think to clearly define what is a chemical versus a chemical reaction. to help us better differentiate between closely related terms, review the words listed here. sort each of the words into the three categories: contains chemicals, chemical reaction, or neither.
Answer:
Chemicals are substances in any form of matter with a chemical composition and property. Chemical reaction involves the combination of two or more different atoms chemically combined together, which are not easily separated.
Explanation:
CHEMICALS
Vitamin [tex]B_{1}[/tex]proteingraniteorangesCHEMICAL REACTIONS
neutralisationcombustionbleachingphotosynthesisNEITHER
sunlightheatrainbow1. Which material had the highest rate of absorption? What can you conclude about the rate
of absorption in the natural world? How might this influence climate regions?
it might be porous materials
Answer:
Air had the highest rate of absorption. Air absorbs most of the suns heat and sun rays and air can move to different areas which are warm and colder.
Explanation:
Potatoes are cut into many parts, making sure that each part has at least one eye (bud). Each piece of potato will usually grow into a new potato plant. Will a new potato plant grow, if planted only with the eye? A. Yes, a full new potato plant can grow from it. B. Yes, but the new plant will take a slightly longer time to germinate. C. No, a new potato plant will not grow because the food needed for germination comes from the potato piece. D. No, a new potato plant will not grow because the leaves emerge only from the potato piece.
Answer:
b
Explanation:
the eye is the most important so it would grow but it will take some time because if we plant it with piece it has some food
CH4 + 2O2 → CO2 + 2H2O In the chemical reaction, if 10 moles of H2O are produced, moles of CO2 are also produced
Answer:
The correct answer is 5 moles of CO2 are produced.
Explanation:
The given reaction:
CH₄ (g) + 2O₂ (g) ⇔ CO₂ (g) + 2H₂O (g)
The given reaction is an illustration of a combustion reaction. Any reaction in which a substance is burnt in excess of oxygen to generate water and carbon dioxide is termed as a combustion reaction. From the given equation, it is clear that the moles of the formation of the products are in the ratio 1: 2, that is, if 10 moles of H₂O is produced, the production of 5 moles of CO₂ will be produced.
Let us multiply, the given equation with 5 we get,
5CH₄ + 10O₂ ⇔ 5CO₂ + 10H₂O
Hence, it is clear that with the formation of 10 moles of H₂O, formation of 5 moles of CO₂ will also take place.
H2SO4 is also called
a. king of acid
b. king of chemical
c. blue vitriol
d. Antacid
Answer:
[tex]\huge\boxed{King\ of \ Acid}[/tex]
Explanation:
H2SO4 (also called sulfuric acid) is also called King of Acids. It is a highly reactive acid.
Answer:
[tex]\large \boxed{\mathrm{a. \ king \ of \ acid }}[/tex]
Explanation:
[tex]\sf H_2SO_4[/tex] or sulfuric acid is known as the king of acid. It is a very reactive acid and is a strong acid in general.
What is the product of the reaction of pentanoic acid with ethanol in the presence of a strong acid?
Answer:
ethylpentanoate
Explanation:
Alkanoic acids react with alkanols in the presence of mineral acids to yield an ester and water. This is the organic analogue of the inorganic neutralization reaction. The reaction his commonly called esterification. It is an acid catalysed reaction.
The reaction of pentanoic acid and ethanol in the presence of a string acid is shown below;
CH3CH2CH2CH2COOH(aq) + CH3CH2OH(aq) ----> CH3CH2CH2CH2COOCH2CH3(aq) + H2O(l)
The name of the compound formed is ethylpentanoate.
Which of the following sequences describes how a four-stroke engine cycle
powers the engine?
Answer: Air and fuel intake, compression and ignition, combustion and expansion, exhaust
Explanation:
Qu
What can you determine about the feasibility of a
reaction if the enthalpy is positive and the entropy is
negative?
1
A. The reaction will usually occur because it is unlikely the
entropy will be greater than the enthalpy.
B. The Gibbs energy will always be positive, and the reaction will
never be feasible.
C. The Gibbs energy will always be negative, and the reaction will
always be feasible.
D. The reaction could be feasible above a certain temperature,
Reset Selection
Answer:
B. The Gibbs energy will always be positive, and the reaction will
never be feasible.
Explanation:
The relationship between gibbs fee energy, G, enthalpy, H and Entropy, S is given as;
ΔG = ΔH - TΔS
If enthalpy is positive and entropy is negative, it means that we are going t always have a positive value for the gibbs free energy.
This means the correct option is option B.
3.Identifica en tu casa 2 elementos en donde sea evidente la elasticidad y dos elementos en los que se manifieste poco y has una pequeña descripción de estos elementos y lo que le permite o no ser evidentemente elásticos
Answer:
Objetos elásticos: forma de cama y neumático de ciclo.
Objetos no elásticos: muebles y cuchara
Explicación:
Dos materiales elásticos que están presentes en las casas son forma y neumático de ciclo y dos materiales no elásticos como muebles y cuchara. Los materiales elásticos son aquellos que muestran alguna deformación en su forma al aplicar fuerza y al eliminar la fuerza, recupera su forma original, mientras que los materiales no elásticos son duros y no pueden cambiar su tamaño y forma.
Me podrían ayudar con esta tarea porfa, paso a paso se los agradecería muchísimo. -El sulfuro de hidrógeno se quema con oxígeno para dar dióxido de azufre y agua. ¿Cuántos moles de dióxido de azufre se forman a partir de la reacción de 0.250 moles de 2 y 0.300 moles de 2? 2h2s(g)+3o2(g)→2so2(g)+2h2o(g)
Answer:
0.2 moles de SO₂
Explanation:
La reaccción es:
2H₂S (g) + 3O₂ (g) → 2SO₂ (g) + 2H₂O(g)
Asumimos que tenemos 0.250 moles de sulfuro y 0.3 moles de oxígeno.
En primer lugar tenemos que averiguar el reactivo limitante.
Si 2 moles de sulfuro de hidrógeno reaccionan con 3 moles de oxígeno, según la reacción.
Entonces 0.250 moles, reaccionarían con (0.250 . 3) /2 = 0.375moles
Tenemos entonces 0.3 moles de oxígeno y necesitamos 0.375 (no nos alcanza). Por lo tanto el O₂ es el limitante y ahora podemos calcular el producto formado. La ecuación nos dice:
3 moles de oxígeno pueden producir dos moles de SO₂
Entonces 0.3 moles (que son los que tenemos) de O₂ producirían:
(0.3 . 2) /3 = 0.2 moles de SO₂
Which of the following is NOT the property of a non-metal? A. Non-rigid structure B. Not ductile C. Low density D. Malleable
Answer:
The answer is D.
Explanation:
Malleable is the property of metal not non-metal.
Answer:
malleable
Explanation:
because a non metal cannot be harmmed into sheetsChemistry is often called the __________ science because it involves the study of the materials in the universe and the changes these materials undergo
Answer:
Central
Explanation:
Chemistry is often called the central science because of connects the physical sciences, life sciences and applied sciences.
Chemistry is the study of matter and changes undergone by matter. This makes chemistry to occupy a central place in many scientific disciplines including medicine, engineering, pharmacy, geology etc. Basic knowledge of chemistry is usually required by experts in these disciplines.
Which are the physical properties of water
Answer:
Some physical properties of water:
It is odorless.It could appear as a white crystalline solid in solid form, a transparent gas with almost no color but a slight hint of blue in liquid form, or a colorless gas in gas form.It has a melting point of 0°C and a boiling point of 100°C.Its density (at 25°C) is about 0.99701 grams/cm³.It has a viscosity of 0.8903 centi-poise.Of course, there are many more but these are some common ones.
How many significant figures are in 0.08260 L? 4 5 6
Answer:
5
Explanation:
Count the digits after the first non zero number, any number after that (even zero) counts.
Hope that helped!!! k
Answer:
[tex]\boxed{4}[/tex]
Explanation:
[tex]\sf Leading \ zeros \ are \ not \ significant.[/tex]
[tex]\sf Trailing \ zeros \ are \ significant.[/tex]
[tex]\sf Non\ zeros \ are \ significant.[/tex]
[tex]0.08260 \sf \ has \ 4 \ significant \ figures.[/tex]
What element is depicted by the following electron configuration:
you can determine this by
adding the numbers of the sub-shells, 2+2+6+2+4=16the number on the last sub-shell, 4 means on the 4th main groupthe 3 before 3p4, tells us on the 3rd period, so the answer is Sulphur.