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2 years ago

In atomic science, the z number refers to the number of __________ in the nucleus of an atom.

1 answer:

6 0

By convention, the symbol Z is assigned to the number of protons in the nucleus, or simply, the atomic number of an element. This is actually used when you want to determine the effective nuclear charge of a specific electron of an element. The equation is:

Z* = Z - S
where
Z* is the effective nuclear charge
Z is the atomic number
S is the number of electrons between the electron in question and the nucleus

There is due to a phenomenon called the shielding effect. This effect states that the farther the electron is from the nucleus, the lesser is its pull of force to the nucleus. That is the reason why the valence electrons (outermost electrons) are the ones always involved in chemicals reactions. Because they are not that strongly bonded to the nucleus of an atom.

You might be interested in

Classify the following reactions into: Element – Element, Element – Compound, Compound – Compound

Rudiy27

Answer:

1. CaO + H₂O ----> Ca(OH)₂

Compound ----- Compound

2. 2 Na + Cl₂ ----> 2 NaCl

Element ----- Element

3. 2 SO₂ + O₂ ----> 2 SO₃

Element ----- Compound

3 0

1 year ago

What is the molarity of a solution in which 0.732 moles of hcl are dissolved in 0.975 liters of solution?

posledela

Molarity is moles divided by liters so do .732 divided by .975 liters.

6 0

2 years ago

Which of the following processes absorbs energy? A) condensation of water on a wind shield of a car B) formation of copperC) bal

Alecsey [184]

Answer:

C) ball rollinflown a hill

Explanation:

The question asks to identify the endothermic process in the list of options. By way of elimination, we have;

A) condensation of water on a wind shield of a car

Condensation is an exothermic process. That is, heat is given out as the gases change into the liquid state of matter.

B) formation of copper

This is an exothermic process. Capture of electrons by a cation is always exothermic.

C) ball rollinflown a hill

This is the correct option. Energy is absorbed by the ball as it moves on the hill

D) formation of ice from liquid water

Freezing is an example of exothermic reaction. Heat is given off to the surroundings.

E) oxide from copper and oxygen

Formation of metal oxides and most reactions involving oxygen are exothermic reactions,

4 0

2 years ago

Which statement best describes the formula equation cl1(g) + 2kbr(aq) —> 2kcl(aq)+br2(i)

Zigmanuir [339]

Answer:

The chlorine gas and potassium bromide solution react to form liquid bromine and potassium chloride solution.

Explanation:

Chemical equation:

Cl₂(g) + KBr (aq) → KCl (aq) + Br₂(l)

Balanced chemical equation:

Cl₂(g) + 2KBr (aq) → 2KCl (aq) + Br₂(l)

This equation showed that the chlorine gas and potassium bromide solution react to form liquid bromine and potassium chloride solution.

Chlorine is more reactive than bromine it displace the bromine from potassium and form potassium chloride solution.

The given equation is balanced and completely hold the law of conservation of mass.

According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.

Explanation:

This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

8 0

2 years ago

Convert 4.5 X 1022 molecules of H2O to moles.

noname [10]

Answer:

<h3>The answer is 0.075 moles</h3>

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

$n = \frac{N}{L} \\$

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

$n = \frac{4.5 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.074750830...$

We have the final answer as

<h3>0.075 moles</h3>

Hope this helps you

3 0

2 years ago