Na22 and Na24 are isotopes
The final temperature : 345 K
<h3>
Further explanation
</h3>
Given
475 cm³ initial volume
600 cm³ final volume
Required
The final temperature
Solution
At standard temperature and pressure , T = 273 K and 1 atm
Charles's Law :
When the gas pressure is kept constant, the gas volume is proportional to the temperature
V₁/T₁=V₂/T₂
Input the value :
T₂=(V₂T₁)/V₁
T₂=(600 x 273)/475
T₂=345 K
Boiling point is the temperature at which a substance begins to change to a gas. Melting point is the temperature at which a substance begins to turn into a liquid. And freezing point is the temperature at which a substance begins turning into a solid.
Answer: Among the listed substances 
is the molecular compound.
Explanation:
A chemical compound formed by the chemical combination of two or more non-metals is called a molecular compound or covalent compound.
For example, Xe and Cl are non-metals. The compound formed by them is which is a molecular compound.
A molecular compound is formed by sharing of atoms between the combining atoms.
Whereas NaF, 
and CaO are all ionic compounds as they are formed by chemical combination of a metal and a non-metal.
Thus, we can conclude that among the listed substances is the molecular compound.
Answer is: 0,0095 mol of hydrogen gas will be produced in reaction.
Chemical reaction: Ca + 2HCl → CaCl₂ + H₂.
m(Ca) = 0,38 g.
n(H₂) = ?
n(Ca) = m(Ca) ÷ M(Ca).
n(Ca) = 0,38 g ÷ 40 g/mol
n(Ca) = 0,0095 mol.
from reaction: n(Ca) : n(H₂) = 1 : 1.
n(H₂) = n(Ca) = 0,0095 mol.
n - amount of substance.
