4.) an element cannot be decomposed by a chemical change, it is a pure substance and no other materials compose it.
The answer would be D carbon dioxide
Answer:C
Explanation: they break apart into ions as they dissolve into solution this process is known as dissociation.
Answer:
The answer to your question is below
Explanation:
a)
Number of atoms = ?
moles of Fe = 4.75
-Use proportions to solve this problem
1 mol of Fe --------------------- 6.023 x 10²³ atoms
4.75 moles --------------------- x
x = (4.75 x 6.023 x 10²³) / 1
x = 2.86 x 10²⁴ / 1
Number of atoms = 2.86 x 10²⁴
b)
Number of moles = ?
moles of 1.058 moles of H₂O
I think this question is incorrect, maybe you wish to know the number of atoms or grams of H₂O.
c)
Number of atoms = ?
moles of Fe = 0.759
1 mol of Fe ------------------ 6.023 x 10²³ atoms
0.759 moles --------------- x
x = (0.759 x 6.023 x 10²³) / 1
x = 4.57 x 10²³ / 1
Number of atoms of Fe = 4.57 x 10²³ atoms
d)
Number of molecules = ?
moles of H₂O = 3.5 moles
1 mol of H₂O ------------------ 6.023 x 10²³ molecules
3.5 moles ------------------ x
x = (3.5 x 6.023 x 10²³) / 1
x = 2.11 x 10²⁴ molecules
Number of molecules = 2.11 x 10²⁴
