How many moles are there in each of 280g of silion

10 moles

Explanation:

of moles = given mass /atomic mass = 280 g /28 g = 10 moles of Si atoms in 280g sample.

10 moles

Explanation:

of moles = given mass /atomic mass = 280 g /28 g = 10 moles of Si atoms in 280g sample

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer