The answer to the question is radium (Ra)
Answer:
c.- How much of the reactants are needed and how much product will made.
Explanation:
The moles is the matter unit used in chemistry to simplify some calculations, instead of using grams. Also the moles are very useful because the chemical reaction can be balanced.
When a Chemical reaction is balanced, then it can be easily to calculate how many moles are necessary to add in a process to obtain a quantity of grams of a product.
C. The temperature decreases because the most energetic molecules escape.
Answer:- There are 32 valence electrons and it's tetrahedral in shape.
Explanations:- Atomic number of carbon is 6 and it's electron configuration is
. It has 4 electrons in the outer most shell means it has 4 valence electrons.
Atomic number of Br is 35 and it's electron configuration is
. It has 7 electrons in the outer most shell(2 in 4s and 5 in 4p) .
There is one C and four Br in the given compound. So, total number of valence electrons = 4+4(7) = 4+28 = 32
Four Br atoms are bonded to the central carbon atom and also there isn't any lone pair present on carbon. It makes it tetrahedral.