Answer:
have the same number of atoms of each element in the reactants and in the products
Explanation:
<em>The basic principle in balancing a chemical equation would simply be to have the same number of atoms of each element in the reactants and in the products.</em>
<u>A balanced chemical equation is one that has the same number of atoms of each element on the reactant and the product's side of the equation.</u> For example, consider the equation below:

On the reactant's side, there are 2 atoms of H and O while there are 2 atoms of H and 1 atom of O on the product's side. This is an imbalanced equation. In order for it to be balanced, the number of atoms of H and O on the reactant side must be equal to the number of H and O on the product side as below.

Answer:
Matter:
toothpaste
gasoline
bacteria
cell
Not matter:
happiness
sound
Explanation:
Matter is something that has mass and volume. Happiness is just a feeling, it doesn't exist in 3d world. Sound is a wave or just the movement of matter (particles of matter). Others have masses and volumes.
Answer:
Q = 3937.56 J
Explanation:
Heat transferred due to change in temperature is given by :

c is the specific heat of water, c=4.18 J/g-°C
We have, m = 15 g, 
So,

Hence, 3937.56 J of heat is transferred.
Answer:
C) 0.457
Explanation:
The ratio between O2 and H2O is 1:2 according to the balanced equation. You can find how many moles is O2 by : 5.12/22.4 = 0.22857 ( 1 mole = 22.4 litters)
Moles of H2O will be 0.22857 * 2 = 0.457142.
Therefore answer C)
Hey buddy I am here to help!
1. C
2. A
3. A & B
4. C
5. C
6. A
7. A
8. A & C
Hope it helps!
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