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
Debora [2.8K]
2 years ago
11

A 50.0 g sample of liquid water at 0.0°c ends up as ice at -20.0°c. How much energy is involved in this change.

Chemistry
1 answer:
ANEK [815]2 years ago
5 0

Answer:

-4200J

Explanation:

Since q = mc∆T

where:

m = mass of the substance

c = specific heat capacity of the substance

∆T = change in temperature in Kelvin

but;

the specific heat capacity of water = 4.2J/K/g

Therefore q = 50*4.2*(253-273)

q = -4200J

Note: the negative is only used to indicate heat loss

Hope this helps

You might be interested in
What physical change happens to atoms and molecules in a solution that is strongly heated in a flame? Is there a phase change? I
Charra [1.4K]

When atoms and molecules speed up or slow down, that is a physical change. When they change state from liquid to solid or from gas to liquid, that is a physical change. ... The ions or molecules can still come back together to form the original substance

6 0
2 years ago
he heat of fusion of tetrahydrofuran is . Calculate the change in entropy when of tetrahydrofuran melts at . Be sure your answer
lana [24]

Answer:

\Delta S=1.8x10^{-3}\frac{kJ}{K}=1.8\frac{J}{K}

Explanation:

Hello.

In this case, given the heat of fusion of THF to be 8.5 kJ/mol and freezing at -108.5 °C, for the required mass of 5.9 g, we can compute the entropy as:

\Delta S=\frac{n*\Delta H}{T}

Whereas n accounts for the moles which are computed below:

n=5.9g*\frac{1mol}{72g} =0.082mol

Thus, the entropy turns out:

\Delta S=\frac{0.0819mol*8.5 kJ/mol}{(-108.5+273.15)K}\\\\\Delta S=1.8x10^{-3}\frac{kJ}{K}=1.8\frac{J}{K}

Best regards.

3 0
3 years ago
What is the relative atomic mass of a hypothetical element that consists isotopes in the indicated natural abundances
belka [17]

The given question is incomplete. The complete question is:What is the relative atomic mass of a hypothetical element that consists isotopes in the indicated natural abundances.

Isotope                    mass amu        Relative abundance

1                                77.9                     14.4

2                               81.9                     14.3

3                               85.9                      71.3

Express your answer to three significant figures and include the appropriate units.

Answer: 84.2 amu

Explanation:

Mass of isotope 1 = 77.9  

% abundance of isotope 1 = 14.4% = \frac{14.4}{100}=0.144

Mass of isotope 2 = 81.9

% abundance of isotope 2 = 14.3% = \frac{14.3}{100}=0.143

Mass of isotope 3 = 85.9

% abundance of isotope 2 = 71.3% = \frac{71.3}{100}=0.713

Formula used for average atomic mass of an element :

\text{ Average atomic mass of an element}=\sum(\text{atomic mass of an isotopes}\times {{\text { fractional abundance}})

A=\sum[(77.9\times 0.144)+(81.9\times 0.143)+(85.9\times 0.713)]

A=84.2amu

Therefore, the average atomic mass of a hypothetical element that consists isotopes in the indicated natural abundances is 84.2 amu

4 0
3 years ago
Why are the molecules of hydrogen chloride gas (hcl) more tightly bound to each other than molecules of oxygen gas (o2)?
Oduvanchick [21]
Answer : If we consider the molecule of oxygen gas which in diatomic state, is bonded to other atom which is of same element this is called as homonuclear.

While in HCl there is a heteronuclear bonding observed because there are two different elements getting involved in the bond formation, also  it creates a electrovalent species in itself and makes it more polar. They are creating a dipole moment by separating different charges in the molecule which cause it to get tightly bonded with each other.
4 0
3 years ago
Sulfuric acid (H2SO4) has a molar mass of 98.1 g/mol. How many oxygen atoms are found in 75.0 g of H2SO4?
nekit [7.7K]

Answer:

18.33 ×10²³ atoms

Explanation:

Given data:

Molar mass of sulfuric acid = 98.1 g/mol

Mass of sulfuric acid = 75.0 g

Number of of oxygen atom present = ?

Solution:

Number of moles of sulfuric acid:

Number of moles = mass/molar mass

Number of moles = 75.0 g/ 98.1 g/mol

Number of moles =0.761 mol

one mole of  sulfuric acid  contain four mole of oxygen atom.

0.761 mol × 4 = 3.044 mol

1 mole = 6.022×10²³ atoms of oxygen

3.044 mol ×  6.022×10²³ atoms of oxygen / 1mol

18.33 ×10²³ atoms

3 0
3 years ago
Other questions:
  • Typically, water runs through the baseboard copper tubing and, therefore, fresh hot water is constantly running through the pipi
    13·1 answer
  • which type of cell is a rose thorn A prokaryotic B eukaryota plant C eukaryotic animal D chloroplastic
    13·2 answers
  • There are many different types of maps a map that shows the types of rocks or the age of rocks in an area is called a
    5·1 answer
  • How many valence electrons does a neutral atom of Argon have
    7·1 answer
  • Starting with the unbalanced equation for the combustion of ethanoic acid, CH3COOH(l)+O2(g)→CO2(g)+?H2O(l) what coefficient shou
    6·1 answer
  • In cellular chemical pathways, the product(s) of any particular reaction are often quickly consumed by the next reaction in the
    5·1 answer
  • What type of combination of two chemicals produces an effect that is equal to their individual effects taken together?
    6·1 answer
  • Chemistry help! Thanks to anyone who helps!
    10·1 answer
  • What is the momentum of a cat of mass 4 kg that is running south with a speed of 1.5 m/s?
    13·2 answers
  • The Density equation is:
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!