Answer:
d
. Sc2O5
Explanation:
Hello,
In this case, when forming oxides from a metal and oxygen, for us to find out each element's subscript, we must exchange them as shown below, considering +5 for scandium:

For that reason, the answer is d
. Sc2O5
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The answer to this would be helium
Answer:
b. 6.02 x 1023 molecules
Explanation:
The formula mass of ammonia is 14 + 1 × 3 = 17.
The number of moles in 27.6g ammonia is 27.6 ÷ 17 = 1.62 mol.
A mole is 6.02 × 10²³, so the number of hydrogen atoms in a 1.62 moles of ammonia is 1.62 × 6.02 × 10²³ × 3 = 2.93 × 10² atoms.
I need you to explain the question
Petroleum is used as a fuel to power vehicles and machines.
Petroleum products include fuel oils for heating and electricity generation.
It is a feedstocks for making the chemicals and plastics.
We use petroleum to produce electricity.