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3 years ago

12

Potassium-40 (40k) is a radioactive isotope of potassium (atomic number 19). how many neutrons are located in the nucleus of pot

assium-40?

1 answer:

sineoko [7]3 years ago

6 0

Number of neutrons = mass number - atomic number = 40 - 19 = 21 answer

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Which statement describes an intensive property of matter

vaieri [72.5K]

An intensive property is a property that does not depend on the amount of the substance in a system being measured. Examples are density and color. The opposite is called extensive where the properties depends on the amount of a substance.

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3 years ago

The complex [Ni(CN)4]2- is diamagnetic and the complex [NiCl4]2- is paramagnetic. What can you conclude about their molecular ge

quester [9]

Answer:

[Ni(CN)4]2- square planar

[NiCl4]2- tetrahedral

Explanation:

For a four coordinate complex such as [Ni(CN)4]2- and [NiCl4]2-, we can decide its geometry by closely considering its magnetic properties. Both of the complexes are d8 complexes which could be found either in the tetrahedral or square planar crystal field depending on the nature of the ligand.

CN^- being a strong field ligand leads to the formation of a square planar diamagnetic d8 complex of Ni^2+. Similarly, Cl^- being a weak field ligand leads to the formation a a tetrahedral paramagnetic d8 complex of Ni^+ hence the answer given above.

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3 years ago

By pushing backwards a roller skater moves forward. This is an example of Newton's

joja [24]

Answer:

newtons law of roller skated duh

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4 years ago

Please Help Me!

S_A_V [24]

Answer:

The answer to your question is SO₂ + 3H₂ ⇒ H₂S + 2H₂O

Explanation:

Reaction

SO₂ + H₂ ⇒ H₂S + H₂O

Reactants Elements Products

1 Sulfur 1

2 Hydrogen 4

2 Oxygen 1

This reaction is unbalanced so we need to balance it.

SO₂ + 3H₂ ⇒ H₂S + 2H₂O

Reactants Elements Products

1 Sulfur 1

6 Hydrogen 6

2 Oxygen 2

Now, the reaction is balanced

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4 years ago

If you feed 100 kg of N2 gas and 100 kg of H2 gas into a

torisob [31]

Answer : The mass of ammonia produced can be, 121.429 k

Solution : Given,

Mass of $N_2$ = 100 kg = 100000 g

Mass of $H_2$ = 100 kg = 100000 g

Molar mass of $N_2$ = 28 g/mole

Molar mass of $H_2$ = 2 g/mole

Molar mass of $NH_3$ = 17 g/mole

First we have to calculate the moles of $N_2$ and $H_2$ .

$\text{ Moles of }N_2=\frac{\text{ Mass of }N_2}{\text{ Molar mass of }N_2}=\frac{100000g}{28g/mole}=3571.43moles$

$\text{ Moles of }H_2=\frac{\text{ Mass of }H_2}{\text{ Molar mass of }H_2}=\frac{100000g}{2g/mole}=50000moles$

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

$N_2+3H_2\rightarrow 2NH_3$

From the balanced reaction we conclude that

As, 1 mole of $N_2$ react with 3 mole of $H_2$

So, 3571.43 moles of $N_2$ react with $3571.43\times 3=10714.29$ moles of $H_2$

From this we conclude that, $H_2$ is an excess reagent because the given moles are greater than the required moles and $N_2$ is a limiting reagent and it limits the formation of product.

Now we have to calculate the moles of $NH_3$

From the reaction, we conclude that

As, 1 mole of $N_2$ react to give 2 mole of $NH_3$

So, 3571.43 moles of $N_2$ react to give $3571.43\times 2=7142.86$ moles of $NH_3$

Now we have to calculate the mass of $NH_3$

$\text{ Mass of }NH_3=\text{ Moles of }NH_3\times \text{ Molar mass of }NH_3$

$\text{ Mass of }NH_3=(7142.86moles)\times (17g/mole)=121428.62g=121.429kg$

Therefore, the mass of ammonia produced can be, 121.429 kg

6 0

3 years ago