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3 years ago

Explain why atoms are neutral.

Chemistry

1 answer:

svlad2 [7]3 years ago

8 0

Atoms are generally neutral because they have an equal amount of protons and electrons.

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What are the chemical names for KF

den301095 [7]

Um, I think it’s: k is potassium and F is fluorine so potassium Fluoride

7 0

3 years ago

How many meters are there in 23.1 miles?

Hunter-Best [27]

Answer:

3.7 ×10⁴ m

Explanation:

We know that,

1 miles = 1609.34 meter

We need to find how many meters are there in 23.1 miles.

23 miles = 37175.85 m

23 miles = 3.7 ×10⁴ m

So, there are 3.7 ×10⁴ m in 23.1 miles.

4 0

3 years ago

A 3.0-L sample of helium was placed in container fitted with a porous membrane. Half of the helium effused through the membrane

zhenek [66]

Explanation:

It is known that rate of effusion of gases are inversely proportional to the square root of their molar masses.

And, half of the helium (1.5 L) effused in 24 hour. So, the rate of effusion of He gas is calculated as follows.

$\frac{1.5 L}{24 hr}$

= 0.0625 L/hr

As, molar mass of He is 4 g/mol and molar mass of $O_{2}$ is 32 g/ mol.

Now,

$\frac{\text{Rate of He}}{\text{Rate of Oxygen}} = \sqrt{\frac{32}{4}$

= 2.83

or, rate of $O_{2} = \frac{\text{Rate of He}}{2.83}$

= $\frac{0.0625 L/hr}{2.83}$

Rate of $O_{2}$ = 0.022 L/hr.

This means that 0.022 L of $O_{2}$ gas effuses in 1 hr

So, time taken for the effusion of 1.5 L of $O_{2}$ gas is calculated as follows.

$\frac{1.5 L}{0.022 L/hr}$

= 68.18 hour

Thus, we can conclude that 68.18 hours will it take for half of the oxygen to effuse through the membrane.

3 0

3 years ago

How many grams of sodium (na ) would be needed to create a 100 millimole concentration in one liter?

Rina8888 [55]

2.3g of sodium would be needed to create a 100 millimole concentration in one liter.

Given,

Mole of Na+ = 100 millimole

As we know that,

1 millimole = 10 -³ mole

Mole of Na+ in 100 millimoles = 100 × 10 -³ mole

= 0.1mole

Mole is defined as the ratio of mass of Na+ to the molar mass of sodium.

<h3>What is Molar Mass? </h3>

The molar mass is defined as the sum of the total mass in grams unit of the atoms present to make a molecule per mole.

Mole of Na+ = mass of Na + / molar mass of Na +

0.1 = mass of Na + / 22.99 gl mol

Mass of Na + = 0.1 × 22.99

= 2.299 g

Mass of Na + = 2.3 g

Thus, we calculated that 2.3g of sodium would be needed to create a 100 millimole concentration in one liter.

learn more about moles:

brainly.com/question/15209553

#SPJ4

7 0

2 years ago

Please help I’ll give you the BRAINLIEST!

Simora [160]

Answer:

1. Number of moles in 3.63 * 10²² atoms of K = 0.06 moles

2. Number of moles in 5.96 g of BaCO₃ = 0.03 moles

3. Number of moles of NH₃ = 0.88 moles

4. Volume of CSI = 0.50 liters

Explanation:

1. One mole of K contains 6.02 * 10²³ atoms

Number of moles in 3.63 * 10²² atoms = (3.63 * 10²² atoms/6.02 * 10²³ atoms) * 1 mole

Number of moles in 3.63 * 10²² atoms of K = 0.06 moles

2. Number of moles = mass / molar mass

Molar mass of BaCO₃ = 197.33 g/mol; mass of BaCO = 5.96 g

Number of moles = 5.96 g/ 197.33 g/mol

Number of moles in 5.96 g of BaCO₃ = 0.03 moles

3. Number of moles = mass / molar mass

Molar mass of NH₃ = 17 g/mol; mass of NH₃ = 1.50 g

Number of moles = 1.50 g/ 17 g/mol

Number of moles of NH₃ = 0.88 moles

4. Chlorosulfonyl isocyanate, ClSO2NCO, otherwise known as CSI, is a reagent used in organic synthesis. It has a density of 1.626 g/cm³.

Volume = mass/density

mass = 82.0 g; density of CSI = 1.626 g/cm³

Volume = 82.0 g / 1.626 g/cm³

Volume = 50.43 cm³

Volume = 50.43 cm³/1000 cm³ * 1 liter

Volume of CSI = 0.50 liters

5 0

3 years ago