Answer:
an oxygen atom with 8 electrons, 8 protons and 9 neutrons
Answer:
1s2 2s2 2p6 3s2 3p6
Explanation:
Calcium is the 20th element. It has 20 electrons in it's neutral state. The electronic configuration is given as;
1s2 2s2 2p6 3s2 3p6 4s2
However in the compound; calcium chloride, it does not exist in it's neutral state.
CaCl2 --> Ca2+ + Cl-
In Ca2+ state, it has lost two electrons, The total number of electrons becomes; 20 - 2 = 18 electrons.
The electronic configuration is given as;
1s2 2s2 2p6 3s2 3p6
Answer:
The answer is:
(a) 
(b) NaCl
(c) 0.211 g
Explanation:
Given:
The mass of NaCl,
= 0.0860 g
The molar mass of NaCl,
= 58.44 g/mol
The volume of
,
= 30.0 ml
or,
= 0.030 L
Molarity of
,
= 0.050 M
Moles of NaCl will be:
= 
= 
= 
now,
Moles of
will be:



(a)
The reaction is:
⇒ 
(b)
1 mole of NaCl react with,
= 1 mol of 
0.0015 mol
needs,
= 
Available mol of NaCl < needed amount of NaCl
So,
The limiting reagent is "NaCl".
(c)
The precipitate formed,
= 
= 
V1/T1=V2/T2
(15.5)/(360K)=(3.6)/(T2)
T2=83.61290K
T2=-189.3871 degrees Celsius