Answer:
Explanation:
Magnesium when it oxidizes has a valence of 2.
Oxygen, when it mixes with something, has a valence of - 2
So Mg and O2 will form something, but what? The answer is MgO
Mg + O2 ===> MgO
To balance this equation, you need 2 Magnesiums on the right and 2 Oxygens also on the right. The left will need a two Magnesiums.
The balanced equation will be
2Mg + O2 ====> 2MgO
Explanation:
For multiplication or division, the rule is to count the number of significant figures in each number being multiplied or divided and then limit the significant figures in the answer to the lowest count.
a. 20.0 meters x 0012.65 meters
The numbers are;
20.0 (3 s.f) and 12.65 (4 s.f)
The multiplication gives; 253
Since 253 is already in 3 s.f, that's the answer.
b. 002.5 × 103 meters + 3.50 × 102 meters
The numbers are;
002.5 (2 s.f), 103 (3 s.f), 3.50 (3 s.f) and 102 (3 s.f)
002.5 × 103 = 257.5 = 260 (2 s.f)
3.50 × 102 = 357 = 360 (2 s.f)
260 + 360 = 620
C. 4 decorated cupcakes.
Because 12 divided by 3 = 4, so you can have 4 cupcakes each with 3 cherries
A for number 1 and C for number 2 im sorry i dont know the rest. :3
