Answer: The closeness, arrangement and motion of the particles in a substance change when it changes state. Materials are a store of internal energy , due to the motion of particles and the chemical bonds between them. When a substance is heated, its internal energy increases: the movement of its particles increases.
Explanation:
You need to find the whole molar mass of the compound using the periodic table to add the values.
Na2CO3= (2 x 23.0) + 12.0 + (3 x 16.0)= 106 g/mol
H2O= 10 x [ (2 x 1.01 ) + (16.0) ]= 180.2 g/mol
the total molar mass is 106 + 180.2 = 286.2 g/mol
the percentage of water you can find by doing "parts over the whole"
H2O%= 180.2 / 286.2 X 100= 63.0%
ans A. 13 to 3
solution:
Total puppies for sale=6
Total puppies left = 2
hence total puppies sold= 6 - 2 = 4
cost of a puppy= $ 104
so cost of 2 puppies = 104 x 4
=416$
Now for kittens:
Total kittens for sale = 12
Total kittens left = 8
hence total kittens sold=12 - 8 =4
cost of a kitten = $24
so cost of 4 kittens= 24x 4=96$
Now ratio of sales of puppies to kittens = 208$/96$
= 13/3 or 13:3 or 13 to 3
I hope this explanation will help you to understand this problem
