Ca №20
N(e)=20
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A= mass number = number of protons and neutrons in the nucleus
Z= number of electrons = number of protons
Given, number of neutrons= 30
Z = A - 30 = 70 - 30 = 40
Z = 40
I hope I was helpful
Answer:
No
Explanation:
Filling a beaker 200ml of water is not bad because Each beaker's capacity may vary according to the size of different beaker.
Answer:
Explanation:
1. Virus's are hard to detect because of their simple construction.
2. Some mutate very easily.
3. It is hard to isolate the virus and kill it without doing damage to the host.
P * V = n R T
<span>1 * 2.50 = n * 0.082 * 273 = 2. 50 / ( 0.082 * 273 ) = 0.11 mol </span>
<span>mass = mole number * molecular mass </span>
<span>mass = 0.11 * ( 16 * 2 ) = 3.52 g </span>