All categories

3 years ago

Write the complete symbol, including mass number and atomic number, for each atom.

Chemistry

1 answer:

Reil [10]3 years ago

8 0

Answer:

a) 58Ni

b) 43Ti

c) 34P

d) 18O

e) 58Ni

f) 43Ti

g)34P

h) 18O

i) 54Cr

Explanation:

<em>a) contains 28 protons and 30 neutrons:</em>

An atom with 28 protons and 30 neutrons has an atomic number of 28 and a mass number of (30+28) = 58.

The atom with atomic number 28 is Ni.

<em>b) contains 22 protons and 21 neutrons:</em>

An atom containing 22 protons and 21 neutrons has an atomic number of 22 and an atomic mass of (22+21) = 43

The atom with atomic number 22 is Titanium (Ti).

This is the 43Ti isotope of titanium

<em>c) contains 15 electrons and 19 neutrons</em>

An atom with 15 electrons would have the same amount of , 15 protons (considering it to be neutral) and has 19 neutrons.

Thus, the atomic number of the atom would be 15 and the mass number would be (15+19) = 34

The atom with atomic number 15 is phosphorus (P).

This is the 34P isotope of phosphorus

<em>d) an oxygen atom with 10 neutrons:</em>

Oxygen has an atomic number of 8, thus there are 8 protons in an atom of oxygen.

The mass number of the oxygen atom with 10 neutrons would be (8+10) = 18

This is 18O - isotope.

<em>e) contains 28 protons and 30 neutrons:</em>

An atom with 28 protons and 30 neutrons has an atomic number of 28 and a mass number of (30+28) = 58.

The atom with atomic number 28 is Ni.

<em>f) contains 22 protons and 21 neutrons:</em>

An atom containing 22 protons and 21 neutrons has an atomic number of 22 and an atomic mass of (22+21) = 43

The atom with atomic number 22 is Titanium (Ti).

This is the 43Ti isotope of titanium

<em>g) contains 15 electrons and 19 neutrons:</em>

An atom with 15 electrons would have the same amount of , 15 protons (considering it to be neutral) and has 19 neutrons.

Thus, the atomic number of the atom would be 15 and the mass number would be (15+19) = 34

The atom with atomic number 15 is phosphorus (P).

This is the 34P isotope of phosphorus

<em>h) an oxygen atom with 10 neutrons:</em>

Oxygen has an atomic number of 8, thus there are 8 protons in an atom of oxygen.

The mass number of the oxygen atom with 10 neutrons would be (8+10) = 18

This is 18O - isotope.

<em>i) The atomic number of Cr is 24 </em>

The mass number is given to be 54.

This is the 54Cr isotope and has 24 protons and 30 neutrons

You might be interested in

What is the charge of an atom after it gains an electron during the formation of a bond?

Alex_Xolod [135]

Answer:

<em>D. One negative charge</em>

Explanation:

During the formation of a bond, if an atom gains an electron, after that it will be left with a negative charge compared to the atom before the bond is formed. This is because in these types of bonds, which are <em>ionic bonds</em>, there is a <em>transfer of electrons between atoms</em>, there will be one or more atoms that yield electrons that will be captured by another and other atoms that gain them, and the difference of charges produced by this transfer of electrons, will cause the union to occur due to the attraction between electrostatic forces.

If you have a neutral atom before joining, and it gains an electron to form a bond,<em> it will have one electron more than its initial state</em> (in the initial state, the number of protons and electrons is the same, because the atoms they are electrically neutral), so having an extra electron will make it have a negative charge, since there will be a difference between the number of protons and electrons that the atom possesses. <em>This is why the correct answer is D. </em>

In the case of <em>response A and B</em>, <em>the atom could only remain positively charged if it loses electrons</em>, but as in this case it wins, <em>they are not correct</em>.

<em>The answer C is also not correct</em> because only one electron wins, so that it is left with two negative charges, <em>it should gain two electrons during the bond formation.</em>

7 0

3 years ago

Bronze is an example of which of the following:<br><br> element<br> atom<br> solution<br> solvent

Brut [27]

It is a solution, because it's the alloy of tin and copper

8 0

3 years ago

All of the following conditions of STP are true except A. 101.3 kPa B. 273.15 K C. 22.4 L D. 3.81 kPa

kaheart [24]

3.81 kpa is the condition which is not true at STP

According to IUPAC the standard temperature and pressure that is STP the temperature is 273.15 k or 0 degrees celsius . and the absolute temperature of 101.325 Kpa or 1 atm. In addition at STP the volume of ideal gas is 22.4

8 0

3 years ago

Large-scale environmental catastrophes _______.

Ymorist [56]

Answer:

D. All of the Above

Explanation:

i just took the test on edgenuity

3 0

3 years ago

28) Consider a 21.0 mL sample of pure lemon juice with a citric acid (H3C6H5O7) concentration of 0.30M. a. How many moles of cir

Damm [24]

<h3>#a. Answer:</h3>

0.0063 mole

<h3>Solution and explanation:</h3>

We are given 21.0 mL citric acid with a concentration of 0.30 M

Part a requires we calculate the number of moles of citric acid.

We need to know how to calculate the concentration of a solution;

Concentration or molarity = Number of moles ÷ Volume of the solution

Thus;

Number of moles = Concentration × Volume

Hence;

Moles = 0.30 M × 0.021 L

= 0.0063 mole

<h3>#b. Answer</h3>

1.21 g citric acid

<h3>Solution</h3>

Part B

We are required to calculate the mass of citric acid in the sample

Number of moles of a compound is calculated by dividing its mass by its molar mass.

Molar mass of Citric acid = 192.124 g/mol

Moles of citric acid = 0.0063 mole

But; Mass = Number of moles × Molar mass

Mass of citric acid = 0.0063 mol × 192.124 g/mol

= 1.21 g citric acid

<h3>#c. Answer</h3>

4.167 mL

<h3>Solution:</h3>

Part C

We are required to determine the initial volume before dilution;

We have;

Initial concentration (M1) = 0.30 M

Final volume (V2) = 250 mL or 0.25 L

Final concentration (M2) = 0.0050 M

Using the dilution formula we can get the initial volume;

Therefore, since; M1V1 =M2V2

V1 = M2V2÷M1

= (0.0050 × 0.25)÷ 0.30

= 0.004167 L or

= 4.167 mL

Therefore, the initial volume of the solution is 4.167 mL

8 0

3 years ago