Answer:
4.5 kilograms of silicon dioxide is required to produce 3.00 kg of SiC.
Explanation:
The balanced equation for the reaction between silicon dioxide and carbon at high temperature is given as:

1 mole silicon dioxide reacts with 3 moles of carbon to give 1 moles of silicon carbide and 2 moles of carbon monoxide.
Mass of SiC = 3.00kg = 3000.00 g
1 kg = 1000 g
Molecular mass of SiC = 40 g/mol
Moles of SiC = 
According to reaction, 1 mole of SiC is produced from 1 mole of silicon dioxide.
Then 75 moles of SiC will be produce from:
of silicon dioxide.
mass of 75 moles of silicon dioxde:

4.5 kilograms of silicon dioxide is required to produce 3.00 kg of SiC.
I think The answer to two is it would sink
Explanation:
it should be option number (D) Iron (III) oxide
Answer:
C
Explanation:
Plants help in carbon dioxode reduction so plants uses atmospheric carbon dioxide and water to produce sugars and oxygen.
HOPE ITS HOPEFUL.
Answer:
PbMg
Explanation:
Because they both have a charge of 2+, they can be reduced and cancel each other out because 2 and 2 can be reduced to 1