Answer: With atomic number 20, calcium atoms have 20 positive protons, and the ion has only 18 electrons, which means the net charge is +2. Calcium ions are essential for muscle contractions, nerve impulses, and bone maintenance.
:
The correct answer is A, B and C
Answer:
0.158 moles
Explanation:
We are given;
9.50 x 10^22 molecules of CO
We are required to determine the number of moles;
We need to know;
1 mole of a compound = 6.022 × 10^23 molecules
Therefore;
9.50 x 10^22 molecules of CO will be equivalent to;
= 9.50 x 10^22 molecules ÷ 6.022 × 10^23 molecules/mole
= 0.158 moles
Therefore, the number of moles are 0.158 moles
Answer:
B, H, E, G, C, D, A, F
Explanation:
The ones closest to the bottom are the oldest
