<span>When a substance changes from one state, or phase, of matter to another we say that it has undergone a change of state, or we say that it has undergone a change of phase. For example, ice melts and becomes water; water evaporates and becomes water vapor.These changes of phase always occur with a change of heat. Heat, which is energy, either comes into the material during a change of phase or heat comes out of the material during this change. However, although the heat content of the material changes, the temperature does not.</span>
The unit expressed in 660 nm of light represents the wavelength of light. If you want to determine the frequency, you use the speed of light to relate the two. The formula is:
c = λν
where
λ is the wavelength
ν is the frequency
c is the speed of light = 3×10⁸ m
Apply SI units:
(3×10⁸ m) = (660×10⁻⁹ m)(ν)
Solving for ν,
<em>ν = 4.55×10¹⁴ s⁻¹</em>
Answer:
Q14: 17,140 g = 17.14 kg.
Q16: 504 J.
Explanation:
<u><em>Q14:</em></u>
- To solve this problem, we can use the relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat absorbed by ice (Q = 3600 x 10³ J).
m is the mass of the ice (m = ??? g).
c is the specific heat of the ice (c of ice = 2.1 J/g.°C).
ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = 100.0°C - 0.0°C = 100.0°C).
∵ Q = m.c.ΔT
∴ (3600 x 10³ J) = m.(2.1 J/g.°C).(100.0°C)
∴ m = (3600 x 10³ J)/(2.1 J/g.°C).(100.0°C) = 17,140 g = 17.14 kg.
<u><em>Q16:</em></u>
- To solve this problem, we can use the relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat absorbed by ice (Q = ??? J).
m is the mass of the ice (m = 12.0 g).
c is the specific heat of the ice (c of ice = 2.1 J/g.°C).
ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = 0.0°C - (-20.0°C) = 20.0°C).
∴ Q = m.c.ΔT = (12.0 g)(2.1 J/g.°C)(20.0°C) = 504 J.
Answer:
Moderate reaction means those reactions which proceed with a measurable rates at the normal room temperature.
22.4L
of any gas contains 1 mol of that gas.
50.75g/10L*22.4L/1 mol= 113.68g/mol- this is the mole weight of your gas
1 mol/113.68g*129.3g=1.137403 mol
Set up a ratio
1.137403mol/x L=1 mol/22.4 L
X=25.477827L, or with sig figs, x=25.5L
