Answer:
Element X with atomic number 10 and atomic mass 21
Element Z with atomic number 10 and atomic mass 22
Explanation:
Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
- Isotopes of an element have the same electronic configuration.
- They share the same chemical properties
- They only differ in their masses.
So, Element X and Z with atomic number 10 which is their number of electrons are isotopes. Their mass number, 21 and 22 differs.
Answer:
87.3 calories of heat is required.
Explanation:
Heat = mcΔT
m= mass, c = specific heat of silver, T = temperature
H= 57.8 g * 0.057 cal/g°C * ( 43.5 - 17 °C)
H = 57.8 * 0.057 * 26.5
H = 87.3069 cal.
The heat required to raise the temperature of 57.8 g of silver from 17 °C to 43.5 °C is 87.3 calories.
Answer:
2Al + 3ZnCl₂ → 3Zn + 2AlCl₃
Explanation:
Chemical equation:
Al + ZnCl₂ → Zn + AlCl₃
Balanced Chemical equation:
2Al + 3ZnCl₂ → 3Zn + 2AlCl₃
This is the example of single displacement reaction. Al displace the zinc and form aluminium chloride and zinc metal.
There are two Al three zinc and six chlorine atoms on both side of equation so it is correctly balanced.
Thus it completely follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Answer:
a. 3.72 [atm]
Explanation:
For a gas at constant temperature, (with no change in number of molecules of the gas), we can apply Boyle's Law: 
![(1.556[atm])(268.5[mL])=P_2(112.4[mL])](https://tex.z-dn.net/?f=%281.556%5Batm%5D%29%28268.5%5BmL%5D%29%3DP_2%28112.4%5BmL%5D%29)
![\dfrac{(1.556[atm])(268.5[mL\!\!\!\!\!\!\!\!{--}])}{112.4[mL \!\!\!\!\!\!\!\!{--}]}=\dfrac{P_2(112.4[mL]\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{-----})}{112.4[mL]\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{-----}}](https://tex.z-dn.net/?f=%5Cdfrac%7B%281.556%5Batm%5D%29%28268.5%5BmL%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B--%7D%5D%29%7D%7B112.4%5BmL%20%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B--%7D%5D%7D%3D%5Cdfrac%7BP_2%28112.4%5BmL%5D%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B-----%7D%29%7D%7B112.4%5BmL%5D%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B-----%7D%7D)
![3.716957[atm]=P_2](https://tex.z-dn.net/?f=3.716957%5Batm%5D%3DP_2)
It seems like the answer should have 4 significant figures since all of the other quantities have 4 significant figures, but the closest answer choice of those provided is a. 3.72
