Answer:
Energy transfers from the metal to the water and calorimeter until they are all at room temperature.
Explanation:
CHECK THE COMPLETE QUESTION BELOW;
A metal sample is heated and placed into the water in a calorimeter at room temperature. Which statement best describes how the calorimeter can be used to determine the specific heat capacity of the metal sample?
Energy transfers to the metal from the water and calorimeter until they are all at room temperature
. Energy transfers from the metal to the water and calorimeter until they are all at room temperature.
Energy transfers to the metal from the water and calorimeter until they all reach a single temperature.
Energy transfers from the metal to the water and calorimeter until they all reach a single temperature.
EXPLANATION;
Using calorimeter to determine the specific heat capacity of the metal sample can be associated to the theory of conservation of energy because heat which is a form of energy is been transfer of heat between the metal to the water and the calorimeter, this process will proceed till single temperature is attained.
The change in the amount of temperature of the water in the calorimeter is measured in order to get the difference in heat change of the calorimeter water.
CHANGE IN HEAT CAN BE CALCULATED USING THE FORMULA.
Q = cmΔT where Q is the change in heat , c is the specific heat capacity and ΔT is the change in temperature
Answer: Option (e) is the correct answer.
Explanation:
A bond that is formed when an electron is transferred from one atom to another results in the formation of an ionic bond.
For example, NaBr will be an ionic compound as there is transfer of electron from Na to Br.
Whereas a bond that is formed by sharing of electrons is known as a covalent bond.
For example, 
will be a covalent compound as there is sharing of electron between carbon and bromine atom.
Also, when electrons are shared between the combining atoms and there is large difference in electronegativity of these atoms then partial charges develop on these atoms. As a result, it forms a polar covalent bond.
For example, in a HBr compound there is sharing of electrons between H and Br. Also, due to difference in electronegativity there will be partial positive charge on H and partial negative charge on Br.
Thus, we can conclude that out of the given options HBr is the only compound that has polar covalent bonds.
Answer: 350 kj/mol
Explanation:
As shown below this expression gives the activation energy of the reverse reaction:
EA reverse reaction = EA forward reaction + | enthalpy change |
1) The activation energy, EA is the difference between the potential energies of the reactants and the transition state:
EA = energy of the transition state - energy of the reactants.
2) The activation energy of the forward reaction given is:
EA = energy of the transition state - energy of [ NO2(g) + CO(g) ] = 75 kj/mol
3) The negative enthalpy change - 275 kj / mol for the forward reaction means that the products are below in the potential energy diagram, and that the potential energy of the products, [NO(g) + CO2(g) ] is equal to 75 kj / mol - 275 kj / mol = - 200 kj/mol
4) For the reverse reaction the reactants are [NO(g) + CO2(g)], and the transition state is the same than that for the forward reaction.
5) The difference of energy between the transition state and the potential energy of [NO(g) + CO2(g) ] will be the absolute value of the change of enthalpy plus the activation energy for the forward reaction:
EA reverse reaction = EA forward reaction + | enthalpy change |
EA reverse reaction = 75 kj / mol + |-275 kj/mol | = 75 kj/mol + 275 kj/mol = 350 kj/mol.
And that is the answer, 350 kj/mol
<u>Given:</u>
Concentration of Ba(OH)2 = 0.348 M
<u>To determine:</u>
pOH of the above solution
<u>Explanation:</u>
Based on the stoichiometry-
1 mole of Ba(OH)2 is composed of 1 mole of Ba2+ ion and 2 moles of OH- ion
Therefore, concentration of OH- ion = 2*0.348 = 0.696 M
pOH = -log[OH-] = - log[0.696] = 0.157
Ans: pOH of 0.348M Ba(OH)2 is 0.157
At STP, also known as standard temperature and pressure, 1 mole of a gas occupies 22.4 L. Since we are given with the volume of 6.3L, we calculate the amount of gas in mol.
n = (6.3L)/ (22.4L/mol) = 0.28125 mol
We are given with the mass of 6.7 g. Therefore, the molar mass or molecular weight of the gas is equal to,
6.7g/0.28125 mol = 23.82 g/mol
