This is true.
The reaction rates are affected by how often the particles collide.
Given is the specific heat of water equal to 4.18 Joule per gram per *C.
This means to raise the temperature of 1 g of water by 1 degree Celsius we need 4.18 joule of energy.
Now, look at the question. We are asked that how much amount of energy would be required to raise the temperature of 25 g of water by (54-50) = 4 degree celsius.
To do so we have formula
Q = m C (temperature difference)
Have a look at pic for answer
<span>Ca has 2 valence electrons and F has 7, they would end up having to share electrons but Ca or F has to keep one because in total there are 9 valence elections and only 8 are needed to make this pair "happy". that's all i can provide. i hope it helped some</span>
Eight because an octet has 8 electrons and when it’s full it’s stable. If it’s not full, it’s constantly sharing or borrowing electrons.