All categories

3 years ago

Problem

Chemistry

1 answer:

postnew [5]3 years ago

4 0

Answer:

C) Potassium, K, and calcium, Ca

Explanation:

Given pair of elements:

Ni and Cu

Potassium and Ca

Nitrogen and oxygen

Solution:

We know that number of protons and number of electrons are always equal and number of electron or number of proton is called atomic number.

Number of protons given elements:

Ni number of protons = 28

Copper number of protons = 29

Combine number of protons = 57

K number of protons = 19

Ca number of protons = 20

Combine number of protons = 39

Ni number of protons = 7

O number of protons = 8

Combine number of protons = 15

Thus, option C is correct.

You might be interested in

How did uranium become present in Earth's upper crust? Choose one: A. It was delivered by comets that crashed into Earth's surfa

Luda [366]

Answer:

Option A. It was delivered by comets that crashed into Earth's surface.

Explanation:

Uranium (U) is a chemical element with atomic number 92.

For many years, a large number of scientists have been studying the abundance and origin of the isotopes of uranium in Earth. According to some theories, the Earth's uranium was produced in one or more supernovae (an explosive brightening of a star), in wich, the main process consists in the rapid capture of neutrons by seed nuclei at great rates. Another theory proposes that uranium is created during the merger of two neutron stars (neutron stars are very dense), because, when such dense bodies come closer together the gravitational force cause them to merge, producing huge amounts of hevy metals like uranium.

Many analyses have been made of the uranium in rocks of the Earth. These measurements shows that the abundance of uranium is bigger in the crust and upper mantle of the Earth.

So, knowing that Earth's uranium was produced through one of these processes, the best answer is option A, the uranium was delivered by comets that crashed into Earth's surface.

Have a nice day!

5 0

3 years ago

1. Caused by movement of rocks below the surface. is Called?

valentina_108 [34]

I don’t know what to do with the answer I don’t know how you feel sorry I didn’t

3 0

3 years ago

The volume of a fixed amount of gas is doubled, and the absolute temperature is doubled. According to the ideal gas law, how has

neonofarm [45]

Answer:

Option A. It has stayed the same.

Explanation:

To answer the question given above, we assumed:

Initial volume (V₁) = V

Initial temperature (T₁) = T

Initial pressure (P₁) = P

From the question given above, the following data were:

Final volume (V₂) = 2V

Final temperature (T₂) = 2T

Final pressure (P₂) =?

The final pressure of the gas can be obtained as follow:

P₁V₁/T₁ = P₂V₂/T₂

PV/T = P₂ × 2V / 2T

Cross multiply

P₂ × 2V × T = PV × 2T

Divide both side by 2V × T

P₂ = PV × 2T / 2V × T

P₂ = P

Thus, the final pressure is the same as the initial pressure.

Option A gives the correct answer to the question.

3 0

3 years ago

80 protons, 119 neutron

g100num [7]

Mercury-199 is composed of 80 protons, 119 neutrons, and 80 electrons.

4 0

2 years ago

In wich situation can a mixture always be called a solution

weeeeeb [17]

A mixture can always be called a solution when its homogeneous.

6 0

3 years ago

Read 2 more answers