Answer:
c. -1020.9 kJ
Explanation:
4Fe (s) + 3 O₂ (g) --> 2 Fe₂O₃(s) ΔH = -826.0 kJ/mol.
atomic weight of iron = 56
69.03 g = 69.03 / 56
= 1.23268 moles
Heat released by 1.23268 moles
= 1.23268 x 826.0
= -1020.9 kJ .
Answer:
Matter:
toothpaste
gasoline
bacteria
cell
Not matter:
happiness
sound
Explanation:
Matter is something that has mass and volume. Happiness is just a feeling, it doesn't exist in 3d world. Sound is a wave or just the movement of matter (particles of matter). Others have masses and volumes.
Answer:
A solution was NOT formed.
Explanation:
For a solution to be formed, the green powder would need to dissolve in the water to form a homogenous mixture. But since the water was cloudy and had lumps of the green powder, it means that the powder did not dissolve, but instead remained insoluble.
Sr will always have 38 protons because that is its atomic number. Normally Sr has 38 protons and 49 neutrons yielding an atomic mass of 87. unless you are dealing with an isotope of Strontium in which 3 additional neutrons would give you the 53 neutrons in your answer, (38p, 52n).
