Yes, you should memorize them. While it is easy to predict them by looking at a periodic table, you should still have a strong grasp of simpler chemistry such as this before more challenging topics are taught.
Answer:
25 possibly
Explanation:
I'm not too sure about this, but sodium oxide is Na2O, 2 sodium and 1 oxygen, so 12.5g * 2 is 25
If someone else comes up with a more convincing argument listen to them
Constant:
Test tubes
Independent:
<span>volume of gas
Dependent:
</span>
<span>amount of H2O2 </span>
