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2 years ago

What is the difference between squares and circles

Chemistry

1 answer:

Natasha2012 [34]2 years ago

7 0

One has 4 edges and one has none.

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Li2SO4 _____ an electrolyte in solution. A. Is B. Is not

Rasek [7]

Answer:

Explanation:

it is an electrolyte because of its strong polar chemical bond

8 0

2 years ago

Read 2 more answers

Calculate the number of moles and the mass of the solute in each of the following solutions:

frosja888 [35]

Answer:

For a: The number of moles of KI are $2.7\times 10^{-5}$ and mass is $4.482\times 10^{-3}g$

For b: The number of moles of sulfuric acid are $1.65\times 10^{-5}$ and mass is $1.617\times 10^{-3}g$

For c: The number of moles of potassium chromate are $2.84\times 10^{-2}$ and mass is 5.51 g.

For d: The number of moles of ammonium sulfate are 39.018 moles and mass is 5155.84 grams.

Explanation:

To calculate the molarity of solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$ .....(1)

To calculate the number of moles of a substance, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(2)

For a:

Molarity of KI = $8.23\times 10^{-5}M$

Volume of solution = 325 mL = 0.325 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

$8.25\times 10^{-5}mol/L=\frac{\text{Moles of KI}}{0.325L}\\\\\text{Moles of KI}=2.7\times 10^{-5}mol$

Now, using equation 2, we get:

Moles of KI = $2.7\times 10^{-5}mol$

Molar mass of KI = 166 g/mol

Putting values in equation 2, we get:

$2.7\times 10^{-5}mol=\frac{\text{Mass of KI}}{166g/mol}\\\\\text{Mass of KI}=4.482\times 10^{-3}g$

Hence, the number of moles of KI are $2.7\times 10^{-5}$ and mass is $4.482\times 10^{-3}g$

For b:

Molarity of sulfuric acid = $22\times 10^{-5}M$

Volume of solution = 75 mL = 0.075 L

Putting values in equation 1, we get:

$22\times 10^{-5}mol/L=\frac{\text{Moles of sulfuric acid}}{0.075L}\\\\\text{Moles of }H_2SO_4=1.65\times 10^{-5}mol$

Now, using equation 2, we get:

Moles of sulfuric acid = $1.65\times 10^{-5}mol$

Molar mass of sulfuric acid = 98 g/mol

Putting values in equation 2, we get:

$1.65\times 10^{-5}mol=\frac{\text{Mass of }H_2SO_4}{98g/mol}\\\\\text{Mass of }H_2SO_4=1.617\times 10^{-3}g$

Hence, the number of moles of sulfuric acid are $1.65\times 10^{-5}$ and mass is $1.617\times 10^{-3}g$

For c:

Molarity of potassium chromate = $0.1135M$

Volume of solution = 0.250 L

Putting values in equation 1, we get:

$0.1135mol/L=\frac{\text{Moles of }K_2CrO_4}{0.250L}\\\\\text{Moles of }K_2CrO_4=2.84\times 10^{-2}mol$

Now, using equation 2, we get:

Moles of potassium chromate = $2.84\times 10^{-2}mol$

Molar mass of potassium chromate = 194.2 g/mol

Putting values in equation 2, we get:

$2.84\times 10^{-2}mol=\frac{\text{Mass of }K_2CrO_4}{194.2g/mol}\\\\\text{Mass of }K_2CrO_4=5.51g$

Hence, the number of moles of potassium chromate are $2.84\times 10^{-2}$ and mass is 5.51 g.

For d:

Molarity of ammonium sulfate = 3.716 M

Volume of solution = 10.5 L

Putting values in equation 1, we get:

$3.716mol/L=\frac{\text{Moles of }(NH_4)_2SO_4}{10.5L}\\\\\text{Moles of }(NH_4)_2SO_4=39.018mol$

Now, using equation 2, we get:

Moles of ammonium sulfate = 39.018 mol

Molar mass of ammonium sulfate = 132.14 g/mol

Putting values in equation 2, we get:

$39.018mol=\frac{\text{Mass of }(NH_4)_2SO_4}{132.14g/mol}\\\\\text{Mass of }(NH_4)_2SO_4=5155.84g$

Hence, the number of moles of ammonium sulfate are 39.018 moles and mass is 5155.84 grams.

3 0

3 years ago

Write the electronic configuration of Cr^2+ (z=24) and predict the number of electrons having n+1 value equal to 3

leonid [27]

Answer:

(a) Cr²⁺: 1s² 2s²2p⁶ 3s²3p⁶ 3d⁴; (b) eight

Explanation:

(a) Electron configuration of Cr

(i). Locate chromium in the Periodic Table.

It's Element 24, so in Period 4, Group 3.

(ii). Write its electron configuration

Remember that Cr is one of those exceptions to the Aufbau principle.

Instead of the predicted electron configuration of [Ar] 4s²3d⁴, we get the configuration [Ar] 4s3d⁵.

The reason is that this this configuration minimizes electron repulsion.

(b) Write the electron configuration for Cr²⁺.

Now, we must remove two electrons from a chromium atom.

The electron in the 4s orbital is removed first, because this orbital is further from the nucleus, making electrons easier to remove.

So, we remove the 4s electron, and then a 3d electron.

The electron configuration of Cr²⁺ is

[Ar]3d⁴ or 1s² 2s²2p⁶ 3s²3p⁶ 3d⁴

(c). Electrons with n + l = 3

The orbitals with n + l = 3 are those covered by the third arrow down in the order of orbital energies:

2p (n = 2, l = 1) and 3s (n = 3, l = 0)

The 2p orbitals can hold six electrons, and the 3s orbital can hold two.

Both subshells are filled in a Cr²⁺ ion, so there are eight electrons

with n+ l = 3.

3 0

3 years ago

(7) need help asappp plss

natima [27]

Answer:

See explanation

Explanation:

The cold drink chiller is a cold substance which is inserted into a bottle of drink which contains warm liquid particles at a particular temperature.

Once the drink chiller is inserted, the liquid molecules around the drink chiller become cooler, denser and sink away from the drink chiller. Other warmer, less dense molecules of the liquid drink now replaces them around the drink chiller.

A convection current is thus set up for as long as the drink chiller is working.

3 0

2 years ago

What is the mass of 2.5 mol of ca, which has a molar mass of g/mol

swat32

Atomic mass Ca = 40 a.m.u

1 mole Ca ----------- 40 g
2.5 mols Ca -------- ( mass Ca )

Mass Ca = 2.5 x 40 / 1

Mass Ca = 100 / 1

= 100 g of Ca

hope this helps!

3 0

2 years ago