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.
Answer:
127.3° C, (This is not a choice)
Explanation:
This is about the colligative property of boiling point.
ΔT = Kb . m . i
Where:
ΔT = T° boling of solution - T° boiling of pure solvent
Kb = Boiling constant
m = molal (mol/kg)
i = Van't Hoff factor (number of particles dissolved in solution)
Water is not a ionic compound, but we assume that i = 2
H₂O → H⁺ + OH⁻
T° boling of solution - 118.1°C = 0.52°C . m . 2
Mass of solvent = Solvent volume / Solvent density
Mass of solvent = 500 mL / 1.049g/mL → 476.6 g
Mol of water are mass / molar mass
76 g / 18g/m = 4.22 moles
These moles are in 476.6 g
Mol / kg = molal → 4.22 m / 0.4766 kg = 8.85 m
T° boling of solution = 0.52°C . 8.85 m . 2 + 118.1°C = 127.3°C
Answer:
they had killed other animals
<h2>Answer: C) 1s²2s²2p⁶</h2>
<h3>Explanation:</h3>
A noble gas has 8 electrons between the p and s orbitals of the outer shell. Helium is the exception because it only has two electrons.
<h3> ∴ 1s²2s²2p⁶ is the noble gas (neon)</h3>
Hope this helps :) I didn’t know how to write subscripts so I wrote it down on some paper.