Answer:- 
molecules.
Solution:- The grams of tetrabromomethane are given and it asks to calculate the number of molecules.
It is a two step unit conversion problem. In the first step, grams are converted to moles on dividing the grams by molar mass.
In second step, the moles are converted to molecules on multiplying by Avogadro number.
Molar mass of 
= 12+4(79.9) = 331.6 g per mol
let's make the set up using dimensional analysis:
= molecules
So, there will be molecules in 250 grams of .
Increasing temperatures in a reaction increases the kinetic energy of the reactant molecules. This causes them to move fast and hence collide with a higher frequency. The higher the rate of collision between the molecules, the faster the reaction.
<span>Mol is the unit of amount of substance. It is equal to 6.02 x 10^23 molecules. Now, One mol of Sodium chloride (NaCl) contains 6.022x 10^23 molecules of NaCl. Also, the number atoms of both Na (sodium) and Cl (chlorine) will be equal. Similatly, One mol of Aluminium Chloride (AlCl3) contains 6.022x 10^23 molecules of (AlCl3) but the ratio of Al and Cl atoms will be 1:3</span>
2. B because it has a lower activation energy.
idk because you have no picture with the lines on it
Here is your answer:
Remember that potential energy is the energy a object has when it's NOT moving, and kinetic energy is when a object has energy when it IS moving. So examples of this kid of transformation would be kicking a soccer ball at first the soccer ball has potential energy because it's not moving but it has potential to move then when someone kicks the soccer ball it has kinetic energy because the ball is not moving.
Example one: when the video first begin "the ball had potential energy and when the ball swung and hit it that potential energy turned into kinetic energy."
Example two: As the video moves on and the two pillars crashed down it caused another ball to move, at first the "ball had potential energy because it was not moving then when the ramp went down it caused the ball to gain kinetic energy."
Example three: At the end of the video the ball push down a row of wooden blocks then lead to it hitting a "bowling ball across the finish line even though the ball moved slowly and not far it still came from potential energy into kinetic energy."
Hope this helps!
