Answer:
D 1 and 3 only I am not sure
Explanation:
Answer:
was difficult to place isotopes of elements as they have the same chemical properties but different atomic masses. It was not possible to predict how many elements could be discovered between two heavy elements as the rise in atomic mass is not uniform.
Answer:
1.006 * 103
Explanation:
Add the number between 1 and 9 and add a decimal accordingly . so the answer is 1.006 multiplied by 10 raised to power 3
Answer:
There are 0.5 mole in 20g of argon.
Explanation:
40 g of argon = 1mole
Then 20g of argon is,
→ 1/40 × 20
→ 0.5 mole
Calcium Chloride would have a charge of +2
Hopes this helps :)