Explain what keeps the electrons confined in the space surrounding the nucleus

2.

Arturiano [62]

Answer:

they are producers and they have means to keep themselves warm

Explanation:

I took test and saw answer.

6 0

2 years ago

Moles/Mass/Molecules Practice Problem Worksheet

Komok [63]

Answer:

Explanation:

1) Convert 11.03 moles of calcium nitrate to grams.

Given data:

Number of moles = 11.03 mol

Mass of calcium nitrate = ?

Solution:

Formula:

Number of moles = mass / molar mass

Now we will rearrange the formula because we have to calculate the mass.

Mass = number of moles × molar mass

Molar mass of calcium nitrate = 164.088 g/mol

Mass = 11.03 mol × 164.088 g/mol

Mass = 1809.89 g

2. How many molecules are contained in 103.4g of sulfuric acid?

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

Given data:

Number of molecules = ?

Mass of sulfuric acid = 103.4 g

Solution:

Formula:

Number of moles = mass / molar mass

Number of moles = 103.4 g/ 98.079 g/mol

Number of moles = 1.05 mol

1 mole = 6.022 × 10²³ molecules

1.05 mol × 6.022 × 10²³ molecules / 1mol

6.323 × 10²³ molecules of sulfuric acid

3. 3.25 x 1024 molecules of dinitrogen pentoxide would be how many moles?

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

Given data:

Number of molecules of dinitrogen pentoxide = 3.25 × 10²⁴

Moles of dinitrogen pentoxide = ?

Solution:

1 mole = 6.022 × 10²³ molecules

1 mol × 3.25 × 10²⁴ molecules / 6.022 × 10²³ molecules

5.4 moles

4. What would be the mass of 9.03 x 1021 molecules of hydrobromic acid?

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

Given data:

Number of molecules of hydrobromic acid = 9.03 × 10²¹

Mass of hydrobromic acid = ?

Solution:

First of all we will calculate the moles of hydrobromic acid.

1 mole = 6.022 × 10²³ molecules

1 mol × 9.03 × 10²¹ molecules / 6.022 × 10²³ molecules

0.015 moles

Mass of hydrobromic acid:

Mass = number of moles × molar mass

Mass = 0.015 mol × 80.9 g/mol

Mass =1.21 g

5. A sample of iron (III) chloride has a mass of 26.29g. How many moles would this be?

Given data:

Number of moles =?

Mass of iron(III) chloride = 26.29 g

Solution:

Formula:

Number of moles = mass / molar mass

Molar mass of iron chloride = 162.2 g/mol

Now we will put the values in formula.

Moles = 26.29 g/ 162.2 g/mol

Moles = 0.16 g

6 0

3 years ago

Assume that there is a puddle that contains 12.0 kg of water and it froze outside since it is -1°C. The

Musya8 [376]

The temperature that must be to freeze the solution would be -21.1 ° C.

<h3>How to calculate the freezing temperature of this solution?</h3>

To calculate the freezing temperature we must take into account the following information.

Solution with a salt concentration of 10% is frozen at -6°C
Solution with a salt concentration of 20% is frozen at -16°C
Solution with a higher concentration is frozen at -21.1°C

According to the above, it can be inferred that the puddle has a 50% concentration of salt because they had 12 kg of water and 6 kg of salt.

So the lowest freezing temperature would be 21.1°C because the puddle is 50% concentrated.

Note: This question is incomplete because there is some missing information. Here is the missing information:

A 10% salt solution freezes at about 20°F (-6°C), and a 20% solution freezes at 2°F (-16°C).
The lowest freezing point obtainable for salt solutions is −21.1 °C

Learn more about freezing in: brainly.com/question/14131507

4 0

2 years ago

Why can a solution be classified as a mixture

Vanyuwa [196]

Because they’re both made up of two substances that are not chemically combined

7 0

3 years ago

Read 2 more answers

Compared to the charge of a proton the charge of an electron has

mart [117]

Answer:

Compared to the charge of proton the charge of an electron is negative.

Explanation:

An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.

All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.

For example

The carbon have six protons and six neutrons so its atomic mass is 12 amu and atomic number is six.

Electron:

The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.

Symbol= e-

Mass= 9.10938356×10-31 Kg

It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.

Neutron and proton

While neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.

Symbol of proton= P+

Symbol of neutron= n⁰

Mass of proton=1.672623×10-27 Kg

Mass of neutron=1.674929×10-27 Kg

5 0

3 years ago