The atmosphere is a mixture of gasses.
When you are asked a question like this, you can always ask yourself this question. Can I change it back after this change? For example, if you are burning wood, you cannot bring it back to wood after you burn it, therefore, it is a chemical change. However, if you boil and evaporate water, you can make the water condense again back into its liquid form. In this case, you cannot bring the tomato back to its raw state. Therefore, cooking raw tomatoes is a chemical change.
Since Group 2 alkali earth metals have 2 valence electrons, they tend to lose those 2 when forming ionic bonds. And the Loss of Electrons = Oxidation (L.E.O. for short). Therefore this group, including Mg and Ca, have an oxidation of [+2].
So the correct answer is C) +2
An not sure,, but maybe 24. don't take my word for it
Answer: C = 0.014M
Explanation:
From n= m/M= CV
m =43.5 M= 148, V=850ml
43.5/148= C× 0.85
C= 0.35M
Applying dilution formula
C1V1=C2V2
C1= 0.35, V1= 25ml, C2=?, V2= 600ml
0.35× 25 = C2× 600
C2= 0.014M
