Answer:

Explanation:
Let recall the crystal structure of CsBr obtains a BCC structure. In a BCC structure, there exist only two atom per cell.
The density d of CsBr in g/cm³ can be calculated by using the formula:

where;
z = 1 mole of CsBr
edge length = 428.7 pm = (4.287 × 10⁻⁸)³ cm
molar mass of CsBr = 212.81 g/mol
avogadro's number = 6.023 × 10²³



The answer is actually A, 1s 2s 2p 3s 3p 4s 3d 4p.
Answer:
1. CO₂ → C + O₂
2. Fe₂ + O₂ → 2FeO
3. 2Al + 3CuO→ Al₂O₃ + 3Cu
Explanation:
1. 1 mol of CO₂ decomposes to 1 mol of C and 1 mol of oxygem
2. 1 mol of Fe₂ reacts with 1 mol of oxygen to produce 2 moles of iron (II) oxide
3. 2 moles of Al, reacts with 3 moles of cupper(II) oxide to produce 1 mol of aluminum dioxide and 3 moles of cupper
When an entire species perishes the species becomes extinct.