Answer:

Explanation:
Hello,
a) In this case, since the heat associated with the dissolution of ammonium nitrate is positive, such reaction is endothermic as it absorbs heat.
b) Now, for computing the temperature once the dissolution is done, we apply (considering that it is a cooling process):

Nonetheless, we should first compute the moles of the mixture as:

Thus, the total absorbed heat is:

Now, the temperature is:

Best regards.

given E = 9.4145E-25
h = 6.626E-34
c = 2.998E8
sub values into the equation above, and solve for wavelength.
You will get 0.211m
A.) The conversion factor is 1 amu =

To know how many amu in

grams of neutrons:

=1.00811 amu
b.) The mass in grams of one lithium ion which has an atomic weight of 6.94 amu.

=

c.) How many amu in 6.492x10^-23g potassium?

= 39.0957 amu
Answer:
Chemical change
Explanation:
From all indicators, Aurelia is seeing a chemical change occurring in the reaction here.
A chemical change is a change in which new substances are produced. For every chemical change:
- they are not easily reversible
- they lead to production of new kinds of substances
- involves mass change
- require considerable amount of energy.
We start off and end with:
Metal + Acid → Black metal + rising gaseous bubbles
Clearly, it is shown that new products are formed and this reaction is impossible to reverse in order to get the reactants back.
This is a typical chemical change.
Answer:
Negative sign says that release of heat.
Explanation:
The expression for the calculation of the heat released or absorbed of a process is shown below as:-
Where,
is the heat released or absorbed
m is the mass
C is the specific heat capacity
is the temperature change
Thus, given that:-
Mass = 25.2 g
Specific heat = 0.444 J/g°C
So,
Negative sign says that release of heat.