Answer:
The diagram shows three isotopes. What element is represented?
A. hydrogen
B. helium
C. lithium
A. hydrogen
A. Is The Correct Answer
what's the atomic weight of salt ?
Answer:
58.44 g/mol
Explanation:
58.44 g/mol
A pupil has drawn the electronic structure of fluorine and the diagram is shown below. However,
mistakes have been made. State three mistakes that have been made.
The first shell can only hold 2 electrons, but the pupil placed in 8 electrons.
The second shell can hold up to 8 electrons, but the pupil only placed in 2 electrons.
Flourine only has 9 total electrons, yet there are 10 electrons in the diagram.
Answer:
Explanation:
In the Fluorine atom there are 2 electrons in the innermost shell and 7 i the outer shell.
PLS HELP!! WILL MARK BRAINLIEST! 99 POINTS!
You're going to first balance the chemical equation.
After that, convert the grams of Na into moles of Na, and then multiply that with the ratio of moles of NaCl to Na, and then convert the mol of NaCl into grams in order to obtain the theoretical yield, since we are given that Na is the limiting reactant.
After that, plug the values into the yield formula, doing some basic algebra, and you should get your result.
You're going to first balance the chemical equation.
After that, convert the grams of Na into moles of Na, and then multiply that with the ratio of moles of NaCl to Na, and then convert the mol of NaCl into grams in order to obtain the theoretical yield, since we are given that Na is the limiting reactant.
After that, plug the values into the yield formula, doing some basic algebra, and you should get your result.
Pesticides and fertilizers are a major cause of
O air pollution
O acid rain
o the greenhouse effect
O groundwater pollution
Answer:
it means air pollution Environment. The chemicals and nutrients found in fertilizers, while beneficial for agricultural crops, can be lethal in high doses for fish, birds and other wildlife. Pesticides, designed to kill pests chemically, are also dangerous when leached into soil or groundwater supplies.
What is the aim of cleaning of the iron nails before doing the experiment?
Assertion (A): An orbital cannot have more than two electrons, moreover, if an orbital has two electrons they must have opposite spins.
Reason (R): No two electrons in an atom can have the same set of all the four quantum
numbers.
a) Both A and R are true and R is the correct explanation of A.
b) Both A and R are true but R is not the correct explanation of A.
c) A is true but R is false.
d) Both A and R are false.
pls answer
Answer:
the correct answer is option ( A )
Both A and R are true and R is the correct explanation of A.
Explanation:
hope it helps you
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Which statement best describes what happens as thermal energy from the
sun warms the pavement?
A. The thermal energy absorbed by the pavement is destroyed.
B. The thermal energy that is not absorbed by the pavement is
destroyed.
C. Some thermal energy is absorbed by the pavement, and some is
destroyed.
D. The thermal energy of the sun is transferred to the pavement.
Answer:
D
Explanation:
The correct answer would be that the thermal energy of the sun is transferred to the pavement.
Thermal energy refers to the internal energy possessed by a system by virtue of the movement of molecules within such a system. In other words, it is the heat energy possessed by a system.
When the thermal energy from the sun warms the pavement, it means that the thermal energy from the sun has been successfully transferred to the pavement. Thermal energy can be transferred by conduction, convection, or by radiation depending on whether the system is a solid, liquid, gas respectively.
The correct option is, therefore, D.
WHICH STATEMENT BEST REPRESENTS A HYPOTHESIS
Answer:
D
Explanation:
Hypotheses are educated guesses, and the best answer is the one with an if, as it indicates that it's a guess.
Answer:
letter b should be the answer
Matty told Harriet that, later that same day, he was going to try to convince her to change her attitude toward the nutritional merits of doughnuts. Based on research findings regarding persuasion, how effective is Matty's strategy?
Answer:
The correct answer is - not very effective; forewarning tends to reduce the effectiveness of an attitude change
Explanation:
The strategy of forewarning or warning before attempting any change in the psychology of an individual is found to be less effective. The subject sees a forewarning seen as a warning that a person is going to attempt to make changes in the attitude of a person about a particular thing or situation.
As a result, the person is ready to defenses up with regard to that idea of persuasion which Builds up defenses for the situation. Therefore, the effect of persuasion is reduced on the person.
Thus, Matty's strategy is not very effective; forewarning tends to reduce the effectiveness of an attitude change
En una carrera de atletismo un deportista se muestra agotado sin fuerzas para continuar y decide abandonar la carrera ¿Que alimentos tomo antes de la carrera ?
Answer:
Los alimentos para evitar la fatiga durante una carrera son alimentos bajos en grasas y altos en carbohidratos, así como alimentos bajos en fibra como pan, mantequilla de maní, plátano, jugo de frutas sin pulpa, y beber hasta aproximadamente 600 ml de líquido aproximadamente 3 horas. antes de la carrera
La comida para comer unos días antes de la carrera incluye carnes magras, arroz, pasta y verduras con contenido de almidón.
Los alimentos que se deben evitar incluyen carne roja, alimentos con alto contenido de grasas saturadas, alimentos fritos, pasteles y salchichas.
Explanation:
What name is given to a metal when it forms an ion, and what type of charge does it have?
Answer:
Cation metal. Positive charge.
Answer:
DHS has been working hard for years and it is still unclear whether this would happen if it is to end the market with the engine is a little less than the next 5years to be 8years in the first quarter and the same year in a quarter or less than a quarter or more than that
Which would increase the reaction rate?
O A. Decreasing the reactant concentrations
B. Removing heat from the system
O C. Adding a catalyst
O D. Lowering the value of k
Answer:
C
Explanation:
C. Adding a catalyst would increase the reaction rate.
What is a catalyst?A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy required for the reaction to occur.
A catalyst enhances the probability of successful collisions between reactant molecules, which raises the pace of the reaction by offering an additional avenue for the reaction to occur.
As there would be fewer reactant molecules accessible to react with one another, decreasing reactant concentrations would result in a slower pace of reaction.
Due to the fact that chemical reactions often require energy to take place, eliminating heat from the system would also slow down the reaction rate. A lower value for k would result in a lower rate constant, which would lower the response rate.
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Sodium is dissolved under kerosene oil or paroffin to protect it from the air. 3) State. Huckle's rule for aromaticity with example. How does benzene react with Chlorine in presense of Sun light
Answer:
His rule states that if a cyclic, planar molecule has 4n+2 π electrons
PLS GUYS ITS FOR 10TH GRADE CHEM
Answer:
1. 2.63x10^6
2. 39.2
Both answers have been rounded
are these following a basic radical or acid radical?
1. Chlorate
2. Peroxide
3. Silver
4. Zinc
5. Nitrite
Answer:
chlorate=Acid
peroxide=Acid
silver=Acid
zinc= Basic
nitrite=Acid
how is electrovalent bond formed ? Describe with an example .
Answer:
For example, the bond between the sodium and chlorine atoms in sodium chloride (NaCl) is formed by the transfer of an electron from sodium to chlorine, creating Na + and Cl – ions. ... The electrostatic attraction between these ions provides the bonding in NaCl.
What's a third reaction? (Chemistry)
Explanation:
a chemical reaction in which the rate of reaction is proportional to the concentration of each of three reacting molecules
A reaction happens quickest during:
A. The beginning of the reaction
B. It is constant throughout the reaction
C. The end of the reaction
D. The middle of the reaction
The reaction is the formation of the product from the reactants. A reaction happens quickest during the beginning of the reaction. Thus, option A is correct.
What are the factors affecting the reaction rate?The reaction rate is the pace at which the reaction takes place and the breakdown or the combination of the reactants to produce the products. The rate of reaction depends on the concentration of the reactants.
The concentration of the reactants is in direct proportion with the rate as at the beginning of a reaction there is a higher amount of substance present than at the end.
As the reaction proceeds, the reactants get consumed and their concentration decreases. As there is a decrease in concentration the rate of the reaction converting and producing the products also decreases.
Therefore, option. the rate of reaction is fast at the beginning.
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what are the defects of mendeleev's periodic table
Answer:
1 Anomalous Pairs. The rest of the pairs of elements don't follow the follow Mendeleev's Principles . they are :
2Grouping of chemically dissimilar elements.
3Position of Isotopes.
4Electronic arrangement.
5Separation of chemically similar elements.
6The position of hydrogen.
I pls help me this is the question:
define the following terms below
Answer:
natural resources: materials or substances such as minerals, forests, water, and fertile land that occur in nature and can be used for economic gain.
renewable resources: a natural resource that is unlimited or that is naturally replenished rather quickly, such as sunlight or water
non renewable resources: (also called a finite resource) is a natural resource that cannot be readily replaced by natural means at a pace quick enough to keep up with consumption.
(answered on edge)
Calculate the percent by mass of each element.
%N = 35 %
%H = 5.0 %
%O = 60 %
Answer:
N=35%. so 35/100*7 =2.45%
H=5.0 so 5/100*1=0.05%
o=60% so 60/100*8=4.8%
hurry
A solution:
A. is a mixture that is made when a solid dissolves and combines with a liquid.
B. is the amount of a substance that will combine with another substance before they begin to chemically combine.
C. is the amount of a substance that will dissolve in 1 dm3 of water at 25 C .
D. is two or more substances that are combined together but not chemically joined.
Reset Selection
Answer:
b is the correct answer ok
A solution is made up of solute and solvent. It is an addition of two or more substances to each other that combines physically and chemically. Thus, option B is correct.
What is a solution?A solution is the mixture of solutes that can be more than one in a solvent that has the same composition all over (homogenous). A solution comprises two main elements called a solute and a solvent.
A solute is the part of the solution that has been added to the solvent for desolvation. On the other hand, the solvent is the substance that dissolves the solute in them to make a solution.
The homogenous mixture or the solution can be created by mixing salt and water, sugar and water, mercury in amalgamated zinc, coffee, vinegar, etc.
Therefore, option B. a solution is the addition of the substances that combine physically.
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What is the order, plz answer
Answer:
C A B
Explanation:
come on, you also know this from normal water waves.
which ones are stronger (= have more energy) ? the small ones or the big ones ?
and the same applies to all waves. the bigger the waves (higher amplitude), the more energy.
Why does the battery give a reading of 9V even though there are no electrons flowing around the circuit?
Answer:
because battery have it's own voltage in it's composition
One the first chemistry test. 12 students got As, 18 students got Bs, and 20 students got Cs.
a. What is the percentage of students received Bs.
b. What is the percentage of students who received Cs?
Express your answer to the ones place.
Answer:
A. 36 percent recieved Bs
B. 40 percent of students received Cs
Explanation:
Amount of students: 12+18+20=50
Students with Bs: (18÷50) x 100 = 36%
Students with C's: (20÷50) x100 = 40%
On the first chemistry test 12 students got A, 18 students got B, and 20 student got C. Thus the percentage of students received B is 0.36 and percentage of students received c is 0.40
What is the percentage of students received B and C?In mathematics, a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign %. A percentage is a dimension less unit and it has no unit.
In above question 12 student got A, 18 student got B, and 20 student got C.
So total number of student = 12 + 18 + 20 = 50.
Then the percentage of students received B is as follows:-
Percentage of students who got B = (student who got B/Total number of student) X 100.
=(18/50) X 100
= 36%
Now percentage of students who got C = (No of students who got C/Total students)X100
=(20/50) X 100
=40%.
Therefore,On the first chemistry test 12 students got A, 18 students got B, and 20 student got C. Thus the percentage of students received B is 0.36 and percentage of students received c is 0.40 percentage of students who got B is 36% and percentage of students who got C is 40%
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Name one diatomic compound which is mononuclei
Answer:
Common diatomic molecules include hydrogen (H2), nitrogen (N2), oxygen (O2), and carbon monoxide (CO). Seven elements exist as homonuclear diatomic molecules at room temperature: H2, N2, O2, F2, Cl2, Br2, and I2. The bond in a homonuclear diatomic molecule is non-polar due to the electronegativity difference of zero.
The process of diffusion can be described as: Movement of water from the area of high concentration of solute to the area of low concentration of solute. Movement of solute from the area of low concentration of solute to the area of high concentration of solute. Movement of water from the area of low concentration of solute to the area of high concentration of solute. Movement of solute from the area of high concentration of solute to the area of low concentration of solute.
Answer:
Movement of water from the area of high concentration of solute to the area of low concentration of solute.
Explanation:
Diffusion can be defined as the movement of gas molecules from a region of high concentration to a region of lower concentration until an equilibrium is attained or reached. This mixing of gas molecules in the liquid or gaseous state is due to their kinetic energy of random motion i.e without requiring bulk motion.
This ultimately implies that, diffusion is a phenomenon through which gas molecules in either a gaseous or liquid state spread out in response to a concentration gradient, which is simply the difference in concentration of the gases across a space.
During diffusion, molecules move from areas of high concentration to areas of low concentration. Also, diffusion does not require energy to move molecules.
Hence, the process of diffusion can be described as movement of water from the area of high concentration of solute to the area of low concentration of solute.
A solute can be defined as a substance that is typically dissolved in a liquid solvent such as water, coffee, tea, etc., to produce a solution.
What is the chemical formula for carbon tetrafluoride?
The Periodic Table
1
mono-
2
di-
3
4
tetra-
5
penta-
hexa-
6
7
hepta-
8
Oct-
9
nano-
10
deca-
which of the following two conditions will favor a spontaneous reaction?
a) an increase in entropy and a decrease in enthalpy
b) an increase in both entropy and in enthalpy
c) a decrease in entropy and a decrease in enthalpy
d) a decrease in entropy and an increase in enthalpy
Two metals with equal mass will absorb heat according to their heat absorbing capacity.
The increase in entropy will cause the solid substance to break into multiple pieces.
When these solute particles detach from each other they will form a solution. Entropy increase will cause the temperature to increase.
Decrease in enthalpy is an exothermic reaction which releases heat from the reaction and then desired products will be formed.
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In a synthesis experiment you obtain a sample of product on which you do a melting point determination and find a melting point range of 114 to 125 degrees Celsius. The sample is supposed to be acetylsalicyclic acid. What preliminary conclusion(s) can you reach from this one determination
Answer:
The melting point determination may need improvement- it may not have been done properly, and make sure it was repeated at least once.
Explanation:
Given that we know the actual melting point of pure acetylsalicyclic acid to be 135°, it follows that the process followed to obtain the melting point range of 114 to 125 degrees Celsius must be inaccurate.
Therefore, we can conclude that, the melting point determination may need improvement. It may not have been done properly, and we must make sure it is repeated at least once.
