All categories

3 years ago

An isotope of an element, atomic number Z, has a mass number 2z+4. How many neutrons are there in the nucleus of the element?

2 answers:

8 0

A) Z + 4

In the actual atom, half of the nucleus would be protons and the other half neutrons, hence the 2z. The additional four in the expression must be neutrons because adding protons would change the element all together.

Wewaii [24]3 years ago

7 0

Answer:

A) Z+4

Explanation:

Atomic number of the isotope = Z

Mass number of the isotope = 2Z+4.

Atomic number = Number of protons in the atom = Number of electrons in the atom

Mass number = Number of protons in the atom + Number of neutrons in the atom

Hence number of neutrons = Mass number - Number of protons

= 2Z + 4 - Z = Z + 4

Hence the required answer to the question is represented by option A which is Z + 4.

You might be interested in

45.0 g of Ca(NO3)2 are used to create a 1.3 M solution. What is the volume of the solution

Stells [14]

As we know that Molarity is given as,

M = moles / V
Solving for V,
V = moles / M ------------------(1)
Also, moles is equal to,
moles = mass / M. mass -------------(2)
puting value of moles from eq. 2 into eq. 1,
V = (mass / M.mass) / M
Putting values,
V = (45 g / 164 g/mol) / 1.3 mol/dm³

V = 0.21 dm³

6 0

3 years ago

A 50.0-g sample of liquid water at 25.0°C is mixed with 35.0 g of water at 89.0°

Scorpion4ik [409]

390 because im cool and awsome

5 0

3 years ago

Explain how/why you categorized the substances the way you did. What characteristics of the substances helped you predict whethe

Rasek [7]

The presence of hydrogen and hydroxyl ions determines the acidic and basic nature of a solution.

<h3>What determine acidic and basic nature of a solution?</h3>

The use of the pH scale is one way of determining the acidic and basic nature of solution. If the pH of a solution is less than 7, it is considered as acidic and if the pH is 7, the solution is neutral.

While if the pH is greater than 7,the solution is basic so we can conclude that the presence of hydrogen and hydroxyl ions determines the acidic and basic nature of a solution.

Learn more about substance here: brainly.com/question/2901507

6 0

2 years ago

The isotope 238U, which starts one of the natural radioactive series, decays first by alpha decay followed by two negative beta

Digiron [165]

Answer: The resulting isotope is $^{231}_{92}\textrm {U}$

Explanation:

Alpha Decay: In this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. The mass number is reduced by 4 units and atomic number is reduced by 2 units.

$^{235}_{92}\textrm{U} \rightarrow ^{231}_{90}\textrm {Th}+^{4}_{2}n$

Beta Decay : It is a type of decay process, in which a proton gets converted to neutron and an electron. This is also known as -decay. In this the mass number remains same but the atomic number is increased by 1.

$^{231}_{90}\textrm{Th}\rightarrow ^{231}_{92}\textrm {Th}+2^{0}_{-1}n$

The resulting isotope is $^{231}_{92}\textrm {U}$

6 0

2 years ago

What mass of silver chloride can be produced from 1.30 L of a 0.245 M solution of silver nitrate? The reaction described in Part

Gnoma [55]

Answer:

Explanation:

Given parameters:

Volume of AgNO₃ = 1.3L

Molarity or concentration AgNO₃ = 0.245M

Unknown:

Mass of AgCl produced = ?

Solution:

To solve this problem, we have to work from the known compound to the unknown one using the mole concept.

The known compound is the one that we can obtain the value of the number of moles from. Here it is the given AgNO₃ that can furnish us with this piece of information;

Now let us establish the balanced reaction equation;

2AgNO₃ + CaCl₂ → 2AgCl + Ca(NO₃)₂

Now;

Find the number of moles of AgNO₃;

Number of moles of AgNO₃ = concentration x volume

= 1.3 x 0.245

= 0.32moles

From the balanced reaction equation;

2 mole of AgNO₃ produced 2 moles of AgCl

0.32 moles of AgNO₃ will produce 0.32moles of AgCl

Now that we know the number of moles of the AgCl, we can find the mass;

Mass of AgCl = number of moles x molar mass

Molar mass of AgCl = 107.9 + 35.5 = 143.4g/mol

Mass of AgCl = 0.32 x 143.4 = 45.89g

5 0

3 years ago