All categories

3 years ago

100 POINTS PLEASE HELP

Chemistry

1 answer:

Evgen [1.6K]3 years ago

7 0

Answer:

1) Molar mass of NaOH can be calculated by taking the atomic mass values in the periodic table. Na (Sodium) = 22.98g/mol, O (Oxygen) = 16g/mol, H (Hydrogen) = 1.01g/mol

Add all the the mass values together for NaOH's molar mass, so (22.98 + 16 + 1.01) = 39.99 or round it to 40g/mol

2) To find the atoms from the moles, you just multiply Avogadro's number (6.02 x 10^23) by the moles.

So 3.35 x (6.02 x 10^23) = 2.0167 x 10^24 atoms are in 3.35 moles of aluminum

3) If the question is asking under standard temperature and pressure, we know that if we divide the volume by the molar volume of a gas (which is 22.7 in standard temperature and pressure), we can get the moles.

So 101.25L / 22.7 = 4.46 mol

4) We know that to find the moles, it is the mass divided by the molar mass. If we rearrange the equation to solve for mass, we have to multiply the moles by the molar mass to get there.

Nitrogen's (N) molar mass on the periodic table is 14g/mol, but since Nitrogen is a diatomic element, it would be N2 by itself. So multiply 14 by 2, which will give you 28g/mol. N2's molar mass is 28g/mol.

Now you multiply 13.7 moles by 28g/mol, which will give you 383.6g

5) Now here I think you may have wrote the question wrong. Molecules would be at a way higher number than just 78.5, so I'm first just going to assume you meant 78.5g.

To get the moles from mass, you divide the mass of the compound by its molar mass. Molar mass of CaCO3 can be just calculated using the atomic mass values for each element in the compound (Ca is 40.07g/mol, C is 14g/mol, O3 would be 16 x 3 g/mol or just 48g/mol) and then adding them all together (40.07 + 14 + 48 = 102.07) which would give us 102.7g/mol.

Now, just divide the mass 78.5g by the molar mass 102.7g/mol

78.5/102.7 = 0.764 moles

Now on the offchance that you were actually referring to molecules, and you accidentally typed a different number doing this, you can find out the moles from the molecules by just dividing the number of molecules you have with avogadro's number (6.02 x 10^23)

So it would look something like this:

molecules of CaCO3 / 6.02 x 10^23

You might be interested in

Water has a high specific heat because: Select one: a. it is a poor insulator b. hydrogen bonds must be broken to raise its temp

Crank

<h2>The required "option is b) hydrogen bonds must be broken to raise its temperature.</h2>

Explanation:

Water has high specific heat due to hydrogen bonds present in it.
The Ionisation of water does not affect the specific heat of the water.
On decreasing the temperature, there is the formation of bonds hence option (d) is wrong.
On increasing the temperature, there is the breaking of bonds hence option (b) is correct.

3 0

4 years ago

Which of the following is the best choice for presenting the percent

Alik [6]

OD

hope this helps!!

3 0

3 years ago

Read 2 more answers

What electron could have quantum numbers n = 2, l = 1, ml = 0, ms = +?

MrMuchimi

Answer is: electron in 2pz orbital.

The principal quantum number is one of four quantum numbers which are assigned to each electron in an atom to describe that electron's state, n=1,2,3... n=2 - the second energy level.
The azimuthal quantum number is a quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital. l = 0,1...n-1, when l = 1, that is p subshell.

The magnetic quantum number, ml, show orbital in which the electron is located, ml = -l...+l, ml = 0 is pz orbital.

The spin quantum number, ms, is the spin of the electron; ms = +1/2 or -1/2.

7 0

3 years ago

What does the last line of the poem suggest

Klio2033 [76]

Answer:

that the poem needs to be finished heh pog

Explanation:

7 0

3 years ago

Read 2 more answers

How does distillation separate a solvent from a solute?

lord [1]

Answer:

Distillable mixtures may contain a solid in a liquid. This method takes advantage of the boiling point of the substances.

In this way, for the distillation to take place correctly, the mixture must be boiled until the boiling point of the solvent is reached, which will then become steam and can be led to a cooled container, in which it will condense and recover its liquidity. On the other hand the solute will remain in the container without alterations; having in both cases pure substances, free of the initial mixture.

5 0

4 years ago