All categories

3 years ago

Help pretty please :)

Chemistry

1 answer:

Hatshy [7]3 years ago

4 0

The answer is 15 bc you multiply the coefficient but the subscript

You might be interested in

A solution is made using 200.0 mL of methanol (density 0.792 g/mL) and 985.1 mL of water (density 1.000 g/mL). What is the mass

DaniilM [7]

Answer: The mass percent of methanol in solution is 13.85 %

Explanation:

To calculate the mass of water, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

For water:

Density of water = 1.000 g/mL

Volume of water = 985.1 mL

Putting values in above equation, we get:

$1.000g/mL=\frac{\text{Mass of water}}{985.1mL}\\\\\text{Mass of water}=(1.000g/mL\times 985.1mL)=985.1g$

For methanol:

Density of methanol = 0.792 g/mL

Volume of methanol = 200.0 mL

Putting values in above equation, we get:

$0.792g/mL=\frac{\text{Mass of methanol}}{200.0mL}\\\\\text{Mass of methanol}=(0.792g/mL\times 200.0mL)=158.4g$

To calculate the mass percent of methanol, we use the equation:

$\text{Mass percent of methanol}=\frac{\text{Mass of methanol}}{\text{Mass of solution}}\times 100$

Mass of solution = [158.4 + 985.1] g = 1143.5 g

Mass of methanol = 158.4 g

Putting values in above equation, we get:

$\text{Mass percent of methanol}=\frac{158.4g}{1143.5g}\times 100=13.85\%$

Hence, the mass percent of methanol in solution is 13.85 %

3 0

3 years ago

Give the nuclide symbol for an atom that has mass number 64 and 35 neutrons.

azamat

The mass number represents the summation of the number of protons and the number of neutrons in the nucleus of an atom.
We are given that the mass number is 64 and that the number of neutrons is 35. Therefore:
number of protons = 64 - 35 = 29 protons

In ground state, number of protons in an atom is equal to the number of electrons. Therefore,
number of electrons = 29 electron

Using the periodic table, we will find that the element that has 29 electrons in ground state is copper.
The nuclide symbol of copper is shown in the attached image.

5 0

4 years ago

To break a chemical bond, energy must be(1) absorbed (2) destroyed (3) produced (4) released

Troyanec [42]

Answer: 1) absorbed

Explanation:

As a chemical bond is formed either by transfer of electrons or sharing of electrons, in order to break the forces of attraction among atoms, energy must be absorbed.

Energy is produced or released when a chemical bond is formed.

Energy is never destroyed, it converts from one form to another.

3 0

4 years ago

Read 2 more answers

How can atoms be neutral if they contain charged particles?

rewona [7]

Stability of atoms is determined by neutron:proton ratio. This n/p ratio is 1:1 for elements below atomic number 20. Hope this helps.

4 0

3 years ago

Blood is maintained at a pH of 7.4 by the primary buffers in the plasma and secondary buffers in the erythrocytes. The plasma co

Alinara [238K]

Answer:

74.456.6.4.7.5.3.33-6.57

Explanation:

4 0

4 years ago