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3 years ago

What mass (in g) of NH3 must be dissolved in 475 g of methanol to make a 0.250 m solution?

Chemistry

1 answer:

Tema [17]3 years ago

5 0

Answer:

We need 2.02 grams of NH3

Explanation:

Step 1: Data given

Mass of methanol = 475 grams

Molality of the solution = 0.250 M

Molar mass of NH3 =17.03 g/mol

Molar mass of = methanol = 32.04g/mol

Step 2: Calculate moles NH3

Molality = 0.250 m = mol NH3 / 0.475 kg

moles NH3 = 0.250 molal * 0.475 kg

Moles NH3 = 0.11875 moles

Step 3: Calculate the mass of NH3

Mass NH3 = moles NH3 * molar mass NH3

Mass NH3 = 0.11875 mol * 17.03 g/mol

Mass NH3 = 2.02 grams

We need 2.02 grams of NH3

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Arrange the following in order of increasing bond strength of the carbon oxygen bond:

icang [17]

Answer: Option (d) is the correct answer.

Explanation:

It is known that length of a bond is inversely proportional to the bond strength. This also means that a single bond has long length due to which it is weak in nature.

And, a double bond is shorter in length and has more strength as compared to a single bond. Whereas a triple bond has the smallest length and it has high strength as compared to a double or single bond.

For example, carbon monoxide is CO where there is a triple bond between the carbon and oxygen atom.

Carbon dioxide is $CO_{2}$ where there exists a double bond between the carbon and oxygen atom.

A carbonate ion is $CO^{2-}_{3}$ when two oxygen atoms are attached through single bond with the carbon atom and another oxygen atom is attached through a double bond to the carbon atom.

Hence, we can conclude that order of increasing bond strength of the given carbon oxygen bond is as follows.

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3 years ago

What is the atomic number of pt-175 after it undergoes alpha decay

DanielleElmas [232]

Answer:

Explanation:

Alpha decay is one of the most basic forms of radioactive decay. It has an atomic mass of 4 and a proton number of two.

Undergoing an alpha decay will decrease the atomic mass by four and the atomic number by two.

In this particular question, we are particular about the atomic number. The atom has an atomic number of 78. So taking 2 off this gives 76

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3 years ago

Consider the following reaction at equilibrium: 2 NH3(g) ⇄ N2(g) + 3 H2(g) What does Le Chatelier's principle predict will happe

BabaBlast [244]

Answer : The equilibrium will shift in the left direction.

Explanation :

Le-Chatelier's principle : This principle states that if any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

The given reaction is:

$2NH_3(g)\rightleftharpoons N_2(g)+3H_2(g)$

As per question, when we are adding $N_2$ then the concentration of $N_2$ is increased on product side then the equilibrium will shift in the direction where decrease of concentration of $N_2$ takes place. Therefore, the equilibrium will shift in the left direction.