Silicon carbide is one of the hardest materials known. It is often known commercially as carborundum. Silicon carbide is used primarily as an abrasive for sandpaper and is manufactured by heating common sand (silicon dioxide, SiO2) with carbon.
- What mass of SiC should result when 1.00x10^3 g of sand is heated with excess carbon?
- What mass of C (in grams) was used to produce the mass of SiC you found above?
PLEAAASEEEE HELP!!!!
SiO2 + 2C ==> CO2 + SiC
mols SiO2 = 1000/molar mass SiO2.
Convert mols SiO2 to mols SiC.
Then g SiC = mols x molsar mass.
Do the same process fore calculating grams C needed.
To solve these problems, we need to use the given information and stoichiometry, which is the relationship between the quantities of substances involved in a chemical reaction.
First, let's write the balanced chemical equation for the reaction:
SiO2 + 3C → SiC + 2CO
From the equation, we can see that 1 mole of SiO2 reacts with 3 moles of C to produce 1 mole of SiC. Now we can use this information to calculate the masses.
1. Calculating the mass of SiC produced:
We are given the mass of SiO2, which is 1.00x10^3 g. To find the mass of SiC produced, we need to convert the mass of SiO2 to moles, and then use the stoichiometry to find the moles of SiC produced, and finally convert back to mass.
First, we need to find the molar mass of SiO2:
- Molar mass of Si = 28.09 g/mol
- Molar mass of O = 16.00 g/mol
Molar mass of SiO2 = (28.09 g/mol) + 2(16.00 g/mol) = 60.09 g/mol
Now, let's calculate the moles of SiO2:
moles of SiO2 = mass of SiO2 / molar mass of SiO2
moles of SiO2 = 1.00x10^3 g / 60.09 g/mol
Next, let's use the stoichiometry to calculate the moles of SiC produced:
1 mole of SiO2 produces 1 mole of SiC
moles of SiC = moles of SiO2
Finally, we can convert the moles of SiC back to mass:
mass of SiC = moles of SiC * molar mass of SiC
Make sure to calculate the molar mass of SiC (molar mass of Si + molar mass of C) before multiplying it with the moles of SiC.
2. Calculating the mass of C used:
From the balanced equation, we know that 3 moles of C react to produce 1 mole of SiC. So the moles of C used will be three times the moles of SiC produced.
moles of C = 3 * moles of SiC
Lastly, we can convert the moles of C back to mass using the molar mass of carbon.
These steps provide a general outline of how to solve the problem. Plugging in the given numbers and performing the calculations should give you the specific answers.