Ramsay is testing the thermal conductivity of four different materials (W, X, Y, and Z) at room temperature. He cuts each material to the same length and touches one end to a 100°C iron cylinder. After 30 seconds, he measures the temperature of the opposite end of each material. His results are shown below. Which material is most likely a metal?
A.
W
B.
X
C.
Z
D.
Y

Here's link to the

tinyurl.com/wpazsebu

The balanced equation will be:
6Mg + P(sub 4) -> 2Mg(sub 3)P(sub 2)
On the right side your Magnesium is 2*3 which equals 6, hence the 6 in front of the Magnesium on the left side. Your Phosphorus on the right side is 2*2 which equals 4, so you do not need another number in front of the Phosphorus on the left side. I hope you have a great day and I hope I helped the understanding behind balancing formulas!!