Answer:
Explanation:
uestion
If an atom of an element has a mass number of 45 and it has 20 neutrons in its nucleus, what is the atomic number of the
element?
Answer is: 550,021 kWh of energy is needed to heat the water
V(water) = 51 gal = 51·3,78 = 189,3 L.
ΔT(water) = 25°C.
d(water) = 1000 g/L.
m(water) = V(water) · d(water)
m(water) = 189,3 L · 1000 g/L
m(water) = 189300 g.
Q = m(water) · ΔT(water) · C(water)
Q = 189300 g · 25°C · 4,184 J/°C·g
Q = 19800780 J = 19800,78 kJ ÷ 3600 = 550,021 kWh.
Hey there!
Protons determine the name of the element you build.
Protons are the particle that determines many things about the element.
The number of protons is the atomic number of an element, which is found on the periodic table.
Hope this helps!
I think the correct answer from the choices listed above is option C. The substances that do not undergo chemical change when mixed are the substances NaNO3(aq) and KI(aq). They form spectator ions. Hope this answers the question.
