The combining of hydrogen and oxygen gas into liquid=H2O (water) is a compound or a molecule because it is 2 different elements combined with chemical bonds so its Chemical. B
Answer: It means that the energy is being stored or preserved to be used at a later time.
Your question was a little vague, so if this isn't the answer you were looking for, just let me know and I'll fix it.
Hope this helps! Good luck! :D
Answer:
450. g of 0.173 % KCN solution contains 779 mg of KCN.
Explanation:
Mass of the solution = m
Mass of the KCN in solution = 779 mg
Mass by mass percentage of KCN solution = 0.173%



1 mg = 0.001 g
m = 450,289 mg × 0.001 g = 450.289 mg ≈ 450. g
450. g of 0.173 % KCN solution contains 779 mg of KCN.
Which of the following measurements is expressed to three significant figures?
C. 5.60 km
Hope this helps!