Answer:
Rb
Alkali Metals are Group 1 so
Rb it isnt Hydrogen because it is a gas
Explanation:
I believe your answer is 23.
Credit: answers.yahoo.com
Hope this helps!
Answer:
False
Explanation:
Atoms only achieve complete outer electron shells if they contain an outer shell with 7 electrons before gaining another electron or an outer shell with 1 electron before losing an electron. This is assuming that the octet-rule can be applied to said atom. In addition, the number of valence electrons varies from atom to atom which is why not ALL atoms achieve complete outer electron shells after gaining or losing just ONE electron.
We use the following formula to calculate the number of atoms:
n (mol) = N(number of atoms) / NA
N(He) = n(mol) · NA
N(He) = 2,0 moles · 6.02·1023 = 12.04·1023 atoms
Answer:
Molarity = 0.4M
Explanation:
Molar mass of NaOH (M)= 40
m= 8g, V= 500ml=0.5L
n= m/M=[8/40]= 0.2mol
Applying
n= CV
0.2= C×0.5
C= 0.4M