1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Naya [18.7K]
3 years ago
13

Calculate the amount of energy when water at 72 degrees c freezes completely at 0 degrees c

Chemistry
1 answer:
gtnhenbr [62]3 years ago
3 0

<u>Answer:</u>

<em>The amount of energy needed when water at 72 degrees c freezes completely at 0 degrees c is 6.37\times10^4 Joules</em>

<em></em>

<u>Explanation:</u>

Q = m \times c \times \Delta T

where

\Delta T = Final T - Initial T

$Q_{1}=100 g \times 4.184 \frac{J}{g^{\circ} \mathrm{C}} \times\left(72^{\circ} \mathrm{C}-0^{\circ} \mathrm{C}\right)$

Q_1 =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)

Q_2  is the heat energy required for the phase change

Q_2 =mass × heat of fusion

\\$Q_{2}=100 g \times 336 \frac{J}{g}$\\\\$Q_{2}=33600 J$

Total heat = Q_1 + Q_2

Total Heat = 30123J + 33600J

= 63725 J

= 6.37\times10^4 Joules is the answer

You might be interested in
Latitude plays a major role in determining the climate, or long-term weather patterns, of an area. Because of differences in the
natima [27]

Answer: B. the curve of earth

Explanation:

The curve of the Earth is tilted as it rotates around the sun. This means that one side will receive more direct sunlight than the other side some parts of the year.

The intensity of solar energy received is directly proportional to the amount of sunlight received so the side receiving more sunlight will receive more solar energy.

This is the same reason Earth has different seasons.

4 0
3 years ago
Calculate the ratio of effusion rates for helium and argon.
lys-0071 [83]

Answer : The ratio of effusion rates for helium and argon is 3.2 : 1

Solution : Given,

Molar mass of Helium = 4 g/mole

Molar mass of Argon = 40 g/mole

Rate of effusion : It is defined as the rate of effusion of a gas is inversely proportional to the square root of the molar mass of the gas.

Formula used :

\text{Rate of effusion}=\frac{1}{\sqrt{M}}

where, M is the molar mass.

\frac{Rate_{He}}{Rate_{Ar}}=\sqrt{\frac{M_{Ar}}{M_{He}}}

Now put all the given values in this expression, we get

\frac{Rate_{He}}{Rate_{Ar}}=\sqrt{\frac{40}{4}}=\frac{3.2}{1}

Therefore, the ratio of effusion rates for helium and argon is 3.2 : 1


4 0
3 years ago
If I add 4 spoons of sugar in one cup of water and add 2 spoons of sugar in another cup of water which one has more density?
OLEGan [10]
The one with 4 spoons of sugar has more density.
4 0
3 years ago
The students want to collect data on how the average kinetic energy of the liquid water molecules in the ice baths changes durin
sergiy2304 [10]

Answer:

C

Explanation:

7 0
3 years ago
An oxidation reaction occurs only in the presence of _____.
aev [14]
The answer is reduction reaction. For every oxidation reaction that takes place, a reduction reaction must also happen, no reduction can occur without oxidation and vice versa. In redox reaction, atoms or ions undergo changes in the electronic structure, involving the transfer of electrons between reactants.
5 0
3 years ago
Other questions:
  • Alpha particle emission occurs when:
    14·1 answer
  • 3. What is meiosis?
    5·1 answer
  • How does matter change from one state to another?
    5·1 answer
  • Chemical formula for an ionic compound
    6·1 answer
  • Which compoud is propanic acid​
    5·1 answer
  • 2FePO4+3 Na2so4---&gt;Fe2(so4) + 2 Na3Po4 if i ise 25grams of iron iii phosphate 18.5 g iton what is my percent yeild?
    8·1 answer
  • How many moles of CO2 will be produced from 43.7 moles of C3H8
    5·1 answer
  • The international space station travels at a distance of about 250 miles above Earth’s surface and at a speed of 17,500 miles pe
    9·1 answer
  • What is the volume of 2.0 mol CO2 at STP?
    6·1 answer
  • A student plots the magnetic field of a bar magnet using a compass the student centers the bar magnet in the middle of a piece o
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!