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3 years ago

Please help!! For a test

Chemistry

1 answer:

irinina [24]3 years ago

7 0

<h3>Further explanation </h3>

Given

Atomic symbol

Required

Atomic composition

Solution

Atomic number = number of protons = number of electrons

Mass Number (A) is the sum of protons and neutrons

Number of protons and Number of Neutrons in nucleus

Number of electrons in the shell

From the picture:

protons = 3

neutrons = 4

electrons = 3

atomic number = protons = electrons = 3

mass number = protons + neutrons = 3+4 = 7

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Which option is an example of a physical property?

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Answer:

Solubility

Explanation:

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Mass percent is one way of expressing concentration of a solution. It is expressed as the mass of solute per mass of solution. For this case, mass percent is calculated as follows:

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Which electron configuration represents a potassium atom in excited state

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Answer: The electronic configuration of potassium atom in excited state is $1s^22s^22p^63s^22p^64s^04p^1$

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There are 2 states classified under energy levels:

1. Ground state: This is the lower energy state which is termed as stable state.

2. Excited state: This is the upper energy state and is termed as the unstable state. All the electrons which are present in this state always come back to the ground state.

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3 years ago

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Suppose a compound is involved in three different reactions denoted R1, R2, and R3. Tripling the concentration of this reactant

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Answer:

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The rate of a chemical reaction is the number of moles of reactants consumed per unit time or the number of moles of products formed per unit. the rate of a chemical reaction is affected by the concentration of reactants

The relationship between the rate of a chemical reaction and the concentration of its reactants is given by the rate law or equation.

Generally, the rate equation is given as;

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For the given reactions R1, R2 and R3

For R1; rate = 3, Concentration = 3[A]

3 = k[A]3ˣ

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Since rate is proportional to concentration, therefore, the order of reaction, x = 1

For R2; rate = 9, Concentration = 3[A]

9 = k[A]3ˣ

3² = k[A]3ˣ

Since rate is proportional to concentration, therefore, the order of reaction, x = 2

For R1; rate = 1, Concentration = 3[A]

1 = k[A]3ˣ

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Since rate is proportional to concentration, therefore, the order of reaction, x = 0

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