Rows are periods, columns are groups
Products
Chemical reactions are characterized by the formation of new products, and the making and breaking of strong chemical bonds.
Answer:
A
Explanation:
Element A has 3 electrons in outermost shell so its valency is 3. It will loose 3 electrons to attain stability, as loss of 3 electrons is easier than gain of 5 electrons.
Valency of B is −2 as it will gain 2 electrons to attain stability and combine with other atom.
Valency of A⟶+3
Valency of B⟶−2
(Refer to Image)
Cross multiply valency of A and B
∴A2B3 compound will be formed.
We have 30% (w/w) HCl this means :
100 g solution contains 30 g HCl
?? g solution contains 7.5 g HCl
By cross multiplication:
Mass of solution =

= 25 g solution
Answer:

Explanation:
To determine the age, we need to know how much U have become Pb, so first we have to calculate the Pb moles present in a sample:


The percentage of U degradation:


Assuming that the life time is linear:

