By looking at the potential energies before and after the reaction, we can tell that the reaction is exothermic (final < initial) or endodermic (final > initial).
Also, the amount of activation energy gives an idea of the external energy required to initiate the reaction (for example, by heating the reactants).
Furthermore, by the same principle, we can also deduce the activation energy for the reverse reaction.
If a catalyst is available, the diagram will show a reduced activation energy, compared to a reaction without catalyst. However, it will also show that the catalyst does not alter the initial and final energies of the reaction.
If you have a lump of solid at its melting point ... like ice at 32°F ...
you have to put a certain amount of heat into it just to change it
to water at 32°F. That amount of heat, that's used just to change
a solid lump into liquid without changing its temperature, is called
the heat of fusion for that substance.
The number is different for every substance.
For water, it takes 336 joules of heat to melt 1 gram of ice
into 1 gram of water, all at 32°F (0°C).
That's an enormous latent heat of fusion ... more than almost any
other known substance. That's why ice is such a good choice
when you need something to put in your drink to cool it down.
Ice absorbs a huge amount of heat before it melts and the drink
gets watered down.
Answer:
D)Not enough information
Explanation:
According to Pascal's principle, the pressure exerted on the two pistons is equal:
Pressure is given by the ratio between force F and area A, so we can write
The force exerted on each piston is just equal to the weight of the corresponding mass: 
, where m is the mass and g is the gravitational acceleration. So the equation becomes
Now we can rewrite the mass as the product of volume, V, times density, d:
We also know that 
So we can further re-arrange the equation (and simplify g as well):
We are also told that block B has bigger volume than block A: 
. However, this information is not enough to allow us to say if the fraction on the right is greater than 1 or smaller than 1: therefore, we cannot conclude anything about the densities of the two objects.
C.) In this, number of Hydrogen atoms is 4
k = 
k = (6.626×10-¹⁹/590 × 10-⁹ )^{2} /2 × 1.673 × 10-²⁷
k = (1.12 × 10-³⁰)^2/3.346×10-²⁷
k = 1.25 × 10-⁶⁰ /3.346×10-²⁷
k = 0
ldk why, my answer is coming this :(
