Answer:
pure hydrogen is a pure substance even though it consists of many different types of molecules. what makes it pure substance is that it is free from contamination.
Answer:
69
Explanation:
hey u said what I said didusbevehdysg
Answer:
Temporary in nature.
No new substance is formed.
Explanation:
Temporary in nature: Does not affect the internal structure of a substance, only the molecules are rearranged.
No new substance is formed: Most of the physical changes are reversible. We can obtain the substance back even after the change.
hope this helps
have an awesome day -TJ
Answer:

Explanation:
25. Boyle's Law
The temperature and amount of gas are constant, so we can use Boyle’s Law.

Data:

Calculations:

26. Ideal Gas Law
We have p, V and n, so we can use the Ideal Gas Law to calculate the volume.
pV = nRT
Data:
p = 101.3 kPa
V = 20 L
n = 5 mol
R = 8.314 kPa·L·K⁻¹mol⁻¹
Calculation:
101.3 × 20 = 5 × 8.314 × T
2026 = 41.57T
