I got 100% on my math test
Our regular teacher is finally back from having a baby. The sub was a good teacher, but he had a realllly nasally voice that so difficult to understand.
Also, on my exam today, we had an extra credit question that looked like this.
Please point out if I did this wrong guys >.<:
Potassium Sulphate + Calcium Phosphate -------> ? + ? Identify reaction type, and balance.
So first, I wrote the formula for the ionic compounds:
K
2S + Ca
3P
2 -------> ? + ?
Being a double replacement chemical reaction, I switched the metals on both sides, and wrote the formulas:
K
2S + Ca
3P
2 ------> K
3P + CaS
So then we have this to balance:
Ca 3 <> Ca 1
P 2 <> P 1
K 2 <> K 3
S 1 <> S 1
So then to balance Calcium, I add 2 CaS atoms to the product, and get:
Ca 3 Ca 3
P 2 P 1
K 2 K 3
S 1 S 3
Now to balance Phosphorus, adding a K
3P atom to the product side:
Ca 3 Ca 3
P 2 P 2
K 2 K 6
S 1 S 3
Finishing it up, I add two more K
2S atoms to the reactant side.
Ca 3 Ca 3
P 2 P 2
K 6 K 6
S 3 S 3
With that done, I get my final answer:
3K
2S + Ca
3P
2 ------>
2K
3P +
3CaS