<u>Answer:</u>
<em>The amount of energy needed when water at 72 degrees c freezes completely at 0 degrees c is
Joules</em>
<em></em>
<u>Explanation:</u>

where
= Final T - Initial T

=30125J
Q is the heat energy in Joules
c is the specific heat capacity (for water 1.0 cal/(g℃)) or 4.184 J/(g℃)
m is the mass of water
mass of water is assumed as 100 g (since not mentioned)
is the heat energy required for the phase change
=mass × heat of fusion

Total heat =
Total Heat = 30123J + 33600J
= 63725 J
=
Joules is the answer
Answer:
un electrón
En la reacción entre el litio y el oxígeno, el litio cede su electrón de valencia al átomo de oxígeno. Como puede verse en la animación de la derecha, dos átomos de litio reaccionan con un átomo de oxígeno. Cada átomo de litio le da un electrón al átomo de oxígeno.
Explanation:
escribí esto hace un tiempo
First write out the balanced equation. 3Cu+2Ag(NO3)3=2Ag+3Cu(NO3)2
Then convert copper from grams to moles
15 g*1 mol cu/63.54 g= 15/63.54 mol cu
Then use the mole ratio to convert Moles Cu to Moles Ag
15/63.54 moles Cu* 2 moles Ag/3 moles Cu
The final awnser is (15*2)/(63.54*3) moles Ag =0.157 moles Ag. If the question wants the answer in grams, convert from moles Ag to grams Ag.
0.157 moles Ag*107.87 g Ag/ mol Ag=16.98 g Ag
B. Most rocks are composed of single mineral
I think the answer is einsteinium is the heavier one here.