Divide mass by the volume to find density.
3. B
4. A
5.A
6. A (i think)
Hope this helps
Density = mass/volume
D = 40/80 = 0.5g
D= 0.5g
<h3>
Answer:</h3>
0.144 moles
<h3>
Explanation:</h3>
- The relationship between mass of a compound, number of moles and molar mass of the compound is given by;
- Number of moles = Mass ÷ Molar mass
- Molar mass is equivalent to the relative formula mass of the compound that is calculated the atomic masses of the elements making the compound.
In this case;
Our compound, KClO3 will have a molar mass of;
= 39 + 35.5 + 4(16)
= 138.5 g/mol
Mass of KClO3 is 20 g
Therefore;
Number of moles = 20 g ÷ 138.5 g/mol
= 0.144 moles
Thus, the number of moles in 20 g of KClO3 is 0.144 moles
