Answer:
15.5 gm
Explanation:
What is the mass of phosphorus that contains twice the number of atoms found in 14 g of iron?
[Relative atomic mass : P = 31; Fe = 56]
14 gm Fe = 14gm/ 56 gm/mole = 14 mole gm/56gm = 14/56 mole
0.25 moles
2 X 0.25 = 0.5 moles
1 mole P = 31 gm
so
0.5 moles P =31/2 =15.5 gm
When magnesium is burned, it reacts with oxygen in air not with the fire. The fire is the energy needed for the reaction to happen. Magnesium reacts with oxygen forming magnesium oxide. The light emitted from the reaction is because the reaction produced a lot of heat.
You must verify that the number of atoms of each type is equal on both sides of the chemical equation: same number of C, same number of H and same number of O on both sides.
<span>A. C4H6 + 5.5O2 ---> 4CO2 + 3H2O
element reactant side product side
C 4 4
H 6 3*2 = 6
O 5.5 * 2 = 11 4*2 + 3 = 11
Then, this equation is balanced.
</span>Do the same with the other equations if you want to verify that they are not balanced.
Answer: option A.
C because it is and I know
1. Berkelium(Berkeley, CA) 2. Dubnium(Dubna, Russia) 3. Darmstaditum (Darmstadt, Germany) 4. Erbium(Ytterby, Sweden) 5. Strontium(Strontian, Scotland) 6. Terbium(Ytterby, Sweden) 7. Yttebium(Ytterby, Sweden) 8. Yttrium(Ytterby, Sweden)