According to my astronomy book, it's about 0.206
The temperature stays the same when a solid changes to a liquid because energy is required to break the forces between particles of water therefore changing the state of matter and separating the particles away from each other.
When a liquid boils, the energy is needed by the particles to escape the surface of the liquid and boil. Instead of raising the temperature, the energy goes into the particles' kinetic energy store so it has enough speed to escape the surface of the liquid.
Answer is: the percent by mass of NaHCO₃ is 2,43%.
m(NaHCO₃) = 10 g.
V(H₂O) = 400 ml.
d(H₂O) = 1 g/ml.
m(H₂O) = V(H₂O) · d(H₂O).
m(H₂O) = 400 ml · 1 g/ml.
m(H₂O) = 400 g.
m(solution) = m(H₂O) + m(NaHCO₃).
m(solution) = 400 g + 10 g.
m(solution) = 410 g.
ω(NaHCO₃) = 10 g ÷ 410 g · 100%.
ω(NaHCO₃) = 2,43 %
It is a column of elements in the periodic table of the chemical elements.
You are given
200 grams of H2O(s) at an initial temperature of 0°C. you are also given the
final temperature of water after heating at 65°C. You are required to get the
total amount of heat to melt the sample. The specific heat capacity, cp, of
water is 4.186 J/g-°C. Let us say that T1 = 0°C and T2 = 65°C. The equation for
heat, Q, is
Q = m(cp)(T2-T1)
Q = 200g(4.186
J/g-°C )(65°C - 0°C)
<u>Q =
54,418J</u>
