Answer:
Alkaline earth metals or akali metals
refer to pic plssss
Answer:
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g 250. mL of a solution is created and has a molarity of 1.50 M. What is the molality of this solution if the volume and density of the pure solvent is about the same as the volume and density of the final solution and the density of the pure solvent is 1.15 g/mL
Answer:
1.30 m
Explanation:
First we calculate the number of moles of solute in the solution, using the definition of molarity:
Molarity = moles / litersConverting 250 mL ⇒ 250 / 1000 = 0.250 Lmoles = 1.50 M * 0.250 L = 0.375 molesThen we calculate the mass of solvent, using the given volume and density:
1.15 g/mL * 250 mL = 287.5 gConverting 287.5 g to kg ⇒ 287.5 / 1000 = 0.2875 kgNow we calculate the molality of the solution:
molality = moles of solute / kg of solvent = 0.375 mol / 0.2875 kgmolality = 1.30 m9) Describe a method that could be used to extract lead from lead oxide (11). You will need
to include charcoal, an ignition (or test) tube and a Bunsen burner. Make sure
you include
each step and what safety measures you would take?
Answer:
Explained below.
Explanation:
In order to extract lead from lead oxide, we need to add carbon from coke to the lead oxide.
We will need;
A bunsen burner
A test tube
Charcoal
First step is to heat charcoal in an oxygen free environment. The safety measure here to ensure an oxygen free environment is to add some zinc metal powder into the test tube in order to remove any atmospheric oxygen inside the container.
Secondly, we will now put charcoal inside the test tube and turn on the bunsen burner to heat it until coke is formed.
Thirdly, we now introduce lead oxide into the coke inside the test tube and the carbon in the coke reacts with the lead oxide to produce lead and carbon dioxide.
Throughout all this process, since we required an oxygen free environment inside the test tube, whenever the test tube is opened, its neck must immediately be warmed by heat with the tube placed in a horizontal direction or very close to being in that horizontal direction so that any movement of air moves outwards from the tube.
what type of properties change ina physical change? Give an example to support your answer?
pls quick who will give the answer first will get the brainliest
Explanation:
We can observe some physical properties, such as density and color, without changing the physical state of the matter observed. Other physical properties, such as the melting temperature of iron or the freezing temperature of water, can only be observed as matter undergoes. A physical change physical change involves a change in physical properties. Examples of physical properties include melting, transition to a gas, change of strength, change of durability, changes to crystal form, textural change, shape, size, color, volume and density.hope it helps.stay safe healthy and happy.The Bohr model of the atom explains why emission spectra are discrete. It could also be used to explain the photoelectric effect. Which is a correct explaination of the photoelectric effect according to the model
Answer:
photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation. The effect is often defined as the ejection of electrons from a metal plate when light falls on it.
(S)-CH3CH(N3)CH2CH2CH3 can be synthesized by an SN2 reaction. Draw the structures of the alkyl chloride and nucleophile that will give this compound in highest yield.
Answer:
See explanation and image attached
Explanation:
Let us recall that the reaction in question is expected to happen by SN2 mechanism. This is because, the reaction occurs at secondary carbon atom and the attacking nucleophile (N3^-) is a good nucleophile.
The reaction occurs via a backside attack of the N3^- ion on (R)-2-chloropentane. This backside attack leads to inversion of configuration at the reaction centre to yield (S)-CH3CH(N3)CH2CH2CH3.
The images of the alkyl halide and nucleophile are shown in the image attached to this answer.
Balance the following reactions and identify the species that have been oxidized and the species that have been reduced.
CL2 +I- -------------> I2 +CL-
WO2 + H2 ---------------> W + H2O
CA + H2O -----------------> H2 + CA(OH)2
AL+ O2 --------------------> AL2O3
Answer:
Balance the following reactions and identify the species that have been oxidized and the species that have been reduced.
CL2 +I- -------------> I2 +CL-
WO2 + H2 ---------------> W + H2O
CA + H2O -----------------> H2 + CA(OH)2
AL+ O2 --------------------> AL2O3
Explanation:
Oxidation is the process where an atom loses electrons.
During oxidation, the oxidation number of the atom increases.
Reduction is the process where an atom gains electrons.
During reduction, the oxidation number of the atom decreases.
The balanced chemical equations for the given reactions are shown below:
[tex]Cl_2 +2I^- -> I_2 + 2Cl^-[/tex]
Iodine undergoes oxidation and chlorine undergoes reduction.
[tex]WO_2 +2 H_2 -> W+ 2 H_2O\\[/tex]
In this reaction, W (tungsten) undergoes reduction and hydrogen undergoes oxidation.
[tex]Ca+2 H_2O ->H_2+Ca(OH)_2\\[/tex]
Ca undergoes oxidation and hydrogen undergoes reduction.
[tex]4Al+3O_2->2Al_2O_3\\[/tex]
Al undergoes oxidation and oxygen undergoes reduction.
which selection is an example of an electrolyte
a. potassium iodide in water
b. sucrose in water
c. pentane in octane
d. methanol in water
Answer:
i believe its A, potassium iodide in water
Explanation:
What quantity of heat is transferred when a 150.0g block of iron metal is heated from 25.0°C to 73.3°C? What is the direction of the heat flow?
The direction of heat flow is increased which means blocks temperature is higher and hotter than it was before
Para formar bronce, se mezclan 150g de cobre a 1100°C y 35g de estaño a 560°C. Determine la temperatura final del sistema.
Dato: Ce Cu: 0,093 cal/gºC; Ce Sn: 0,060 cal/gºC
Answer:
[tex]T_F=1029\ºC[/tex]
Explanation:
¡Hola!
En este caso, dada la información, es posible determinar que la temperatura del sistema estará entre 560 °C y 1100 °C, por lo tanto, se hará necesario establecer la suma de la energía del cobre y del estaño como cero:
[tex]Q_{Cu}+Q_{Sn}=0[/tex]
Así, podremos escribir esta ecuación en términos de masas, calores específicos y temperaturas como sigue:
[tex]m_{Cu}C_{Cu}(T_F-T_{Cu})+m_{Sn}C_{Sn}(T_F-T_{Sn})=0[/tex]
Con el fin de resolver para la temperature final:
[tex]T_F=\frac{m_{Cu}C_{Cu}T_{Cu}+m_{Sn}C_{Sn}T_{Sn}}{m_{Cu}C_{Cu}+m_{Sn}C_{Sn}}[/tex]
Así, reemplazamos las variables conocidas como se muestra a continuación:
[tex]T_F=\frac{150g*0.093cal/g\ºC*1100\°C+35g*0.060cal/g\ºC*560\°C}{150g*0.093cal/g\ºC+35g*0.060cal/g\ºC}\\\\T_F=1029\ºC[/tex]
¡Saludos!
what is the machine used to check melting point called?
Answer:
Melting-point apparatus
Consider an acid-base titration in which the base is dispensed from a burette into a flask containing an acid. If any drops of the base adhere to the inner walls of the flask, but do not actually mix with the solution, the calculated acid concentration would be
Answer:
Higher than the actual value
Explanation:
Titration is a volumetric process in which a known volume of solution is dispensed from a burette to react with a known volume of solution in a conical flask.
When acid-base titration is carried out in such a way that the base is in the burette and the acid is in the conical flask and drops of the base adhere to the inner walls of the flask, but do not actually mix with the solution, the calculated acid concentration would be higher than the actual value.
This is because;
From CA= CBVBnA/VAnB
When VB(volume of base) that reacted is lower than the actual volume recorded, then the calculated volume of CA(concentration of acid) is much higher than the actual value since drops of the base adhere to the inner walls of the flask.
3. Does entropy increase or decrease in the following processes?
A. Complex carbohydrates are metabolized by the body, converted into simple sugars.
Answer: Increase
es-lesund
B. Steam condenses on a glass surface.
Answer:
decreare
-->
MgCl2(s)
C. Mg(s) + Cl2(g)
correct
Answer:
Answer:
HOPE IT helps much as you can
b) What is the change in entropy of the reaction if ΔH° = -3.2 kJ mol-1?
How many ozone molecules can each chlorine atom in the stratosphere destroy
Answer:
100,000
Explanation:
1 or 2 topics or two lessons should be explained in an illustrated childrens book minimum of 10 pages must have 3 or more sentences
Answer:
Yes because same topic are long
A cation is a
negative electrode.
negatively charged ion.
positively charged ion.
positive electrode
Answer:
Each electrode attracts ions that are of the opposite charge. Positively charged ions, or cations, move toward the electron-providing cathode, which is negative; negatively charged ions, or anions, move toward the positive anode.
show in chemistry the fermentation of carbohydrate to form alcohol
hope it helps to everyone
Which pairs of aqueous solutions will not produce a precipitate when mixed AgNo3(aq) and NaCl(aq)?
Answer:
CHCI3
Explanation:
there are no free CI ions hence it doesnt precipitate with an aqeous solution of AQUO33
The volume of a single tantalum atom is 1.20×10-23 cm3. What is the volume of a tantalum atom in microliters?
Answer:
1.20x10⁻²⁰μL
Explanation:
1cm³ is equal to 1milliliter. As we must know, 1milliliter = 1000 microliters, 1000μL. To convert the 1.20x10⁻²³mL we need to use the conversion factor: 1mL = 1000μL.
The volume of tantalum in μL is:
1.20x10⁻²³mL * (1000μL /1L) = 1.20x10⁻²⁰μL
according to the kinetic molecular theory what happens to a liquid when it is transferred from one container to another
Answer:
See explanation
Explanation:
Liquids are known to have a definite volumes but not a definite shape. This means that a liquid takes on the volume of the container in which it is found.
Hence, when a liquid is transferred from one container to another, the volume of the liquid remains the same but the shape of the liquid changes.
This happens when the two containers do not possess the same shape.
this was in my science test just want to see if anyone knows?? the wording is so confusing
the relative atomic mass of an element compares the mass of an atom of an element with the mass of an atom of.......
Answer:
the molar mass of the element
Predict the products of each reaction, and whether the solution at equilibrium will be acidic, basic, or neutral.1. P4O10 + 6H2O (l)---->2. Na2O + H2O(l) ------>3. N2O5 + 3H2O (l)------>
Answer:
For 1: The product is phosphoric acid and the solution is acidic in nature.
For 2: The product is sodium hydroxide and the solution is basic in nature.
For 3: The product is nitric acid and the solution is acidic in nature.
Explanation:
For the given options:
(1): When diphosphorus pentoxide reacts with water, it leads to the formation of phosphoric acid, which makes the solution acidic in nature.
The chemical equation for the reaction follows:
[tex]P_4O_{10}+6H_2O(l)\rightarrow 4H_3PO_4(aq)[/tex]
(2): When disodium oxide reacts with water, it leads to the formation of sodium hydroxide, which makes the solution basic in nature.
The chemical equation for the reaction follows:
[tex]Na_2O+H_2O(l)\rightarrow 2NaOH(aq)[/tex]
(3): When dinitrogen pentoxide reacts with water, it leads to the formation of nitric acid, which makes the solution acidic in nature.
The chemical equation for the reaction follows:
[tex]3N_2O_5+3H_2O(l)\rightarrow 6HNO_3(aq)[/tex]
A student dropped a piece of nickel metal into a solution of HCl(aq). He observed the formation of gas bubbles and collected the gas into another test tube. The student performed a splint test and observed that the splint flared up when he placed the splint into the test tube of the gas. What can be said about the results of this students experiment?
a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.
b. The experiment was performed incorrectly. Nickel doesn't react with HCl. Therefore, the student picked up the wrong metal when conducting the experiment.
c. The student completed the experiment correctly and there were no errors in the experiment.
d. The student performed the splint test incorrectly. He should of observed the flame being extinguished when the splint was placed in the test tube.
Answer:
a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.
Explanation:
It is given that a student performed an experiment where he dropped a nickel metal in to HCl solution. He observed the reaction and performed a splint test in the test tube that is filled with a gas which is formed while Nickle is dropped into the solution of HCl.
But the experiment that the student performed was incorrect. He must have observed the popping sound when the splint was placed in the test tube.
When the splint was added to the gas splint flared up. The hydrogen gas pops out when exposed to the flame.
[tex]$Ni + HCl(aq) = NiCl + H_2$[/tex]
Thus the correct option is (a).
Each of the following sets of quantum numbers is supposed to specify an orbital. Choose the one set of quantum numbers that does NOT contain an error.
a. n = 4, l = 3, ml =-4
b. n = 2, l = 2, ml =0
c. n = 3, l = 2, ml =-2
d. n = 2, l = 2, ml =+1
Answer:
n = 3, l = 2, ml =-2
Explanation:
Quantum numbers are a set of values which can be used to describe the energy and position of an electron in space.
There are four sets of quantum numbers;
1) principal quantum number
2) orbital quantum number
3) spin quantum number
4) magnetic quantum number.
The values of orbital quantum number include; -l to +l;
The set of quantum numbers without error is ; n = 3, l = 2, ml =-2
What change would increase the amount of solid solute able to be dissolved in liquid water?
Decreasing rate of stirring
Decreasing surface area
Increasing pressure
Increasing temperature
Answer:
D: Increasing temperature
Explanation:
From collision theory, we know that the more the increase in collisions, the faster the rate of the chemical reaction.
Now, the amount of solid solute in a solvent will change with a corresponding change in temperature. What we mean is that, the higher the temperature increases, the higher the number of collisions between the solvent molecules as well as leading to an increase in the solute particles which will mean an increase in the amount of the solid solute dissolved. The correct answer is option D.
Answer:
Increasing temperature.
Explanation:
Which one of the following compounds does NOT obey the "octet rule"?
LiF
BF3
H20
CBr4
Answer:
BF3
Explanation:
The octet rule describes atoms' preference and affinity for having eight (8) electrons in their valence shell. Whenever an atom is encircled by eight(8) electrons, it forms a stable configuration. This octet can be composed of its' own electrons as well as some shared electrons. In the periodic table, only the s-block and p-block electrons are considered for the octet rule.
However, out of the given option, only BF3 does not comply with the octet rule: This is because the Bromine contains 2 lone pairs of electrons and 3 other shared bonded pairs of electrons with Flourine making a total of 10 electrons in the valence shell and which does not conform with the octet rule.
Consider the balanced chemical equation below.
2 A ⟶ C + 4 D
How many moles of D would be produced if 6 moles of A were used?
Explanation:
[tex]here \: is \: your \: explanation : - \\ \\ given \: balanced \:equation \: = > \\ \\ 2 A=>C \: + \: 4D \\ \\ by \: this \: equation \: we \: get \: \\ \\ 2 \: moles \: of \: A \: produce \: 4 \: moles \: \\ \\ of \: D \\ \\ hence \: . \: 1 \: mole \: can \: produce \: = 4 \div 2 \\ \\ = > 2 \: moles \: \\ \\ so \: if \: 6 \: moles \: of \: A \: used \: then \: \\ \\ amount \: of \: D \: produced \: = (6 \times 2) \\ \\ = > 12 \: moles \: of \: D \\ \\ \mathcal\blue{ Hope \: it \: helps \: you \: (. ❛ ᴗ ❛.) }[/tex]
Please help me, I don't bite. 3.
Answer:
jjjjjjjjj
Explanation:
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"All plants perform photosynthesis. The cactus on my windowsill is a plant, therefore it must be performing photosynthesis." This statement is an example of:
Group of answer choices
Deductive Reasoning
Logical Fallacy
Inductive Reasoning
Bias
Answer:
Deductive reasoning