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2 years ago

How many molecules are in 69 grams of Na?

1 answer:

7 0

Molar mass Na = 23.0 g/mol

1 mol ---- 23.0 g
n mol ---- 69 g

n = 69 / 23.0

n = 3.0 moles

1 mole -------- 6.02x10²³ molecules
3.0 moles ---- ?

3.0 * 6.02x10²³ / 1

= 1.806x10²⁴ molecules

hope this helps!

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Heterogeneous mixtures are throughout, while homogeneous mixtures are throughout.

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Answer:

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Homogeneous Mixtures

A homogeneous mixture is a mixture in which the composition is uniform throughout the mixture. The salt water described above is homogeneous because the dissolved salt is evenly distributed throughout the entire salt water sample. Often it is easy to confuse a homogeneous mixture with a pure substance because they are both uniform. The difference is that the composition of the substance is always the same. The amount of salt in the salt water can vary from one sample to another. All solutions would be considered homogeneous because the dissolved material is present in the same amount throughout the solution.

One characteristic of mixtures is that they can be separated into their components. Since each part of the mixture has not reacted with another part of the mixture, the identities of the different materials is unchanged.

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2 years ago

A 13.00 g sample of citric acid reacts with an excess of baking soda as shown in the equation. What is the theoretical yield of

julia-pushkina [17]

Chemical equation of the reaction between citric acid and baking soda:

$C_{6} H_{8} O_{7} +3NaHCO_{3} -\ \textgreater \ Na_{3} C_{6} H_{5} O_{7} +3 H_{2} O+3CO_{2}$

Ratios

Citric Acid Baking soda -> Sodium Citrate Water Carbon Dioxide
C6H8O7 CO2
1 mole 3moles

Molecular masses
Citric acid
6*12 + 8*1 + 7*16 = 192 g/mole
Carbon dioxide
12 + 2*16 = 44 g/mole

Proportion carbon dioxide / citric acid

3 * 44 g of carbon dioxide / 192 g of citric acid

132 g of carbon dioxide / 192 g of citric acid

13.00 g of citric acid * [132 g of carbon dioxide / 192 g of citric acid] = 8.94 g of carbon dioxide.

Answer: 8.94 grams.

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3 years ago

Read 2 more answers

The human body can get energy by metabolizing proteins, carbohydrates or fatty acids, depending on the circumstances. Roughly sp

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Answer:

the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose is 1.0111

Explanation:

Given the data in the question;

To determine the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose, first we get the molar masses of both alanine and glucose

we know that;

Molar mass of alanine ( C₃H₇NO₂ ) = 89.09 g/mol

Molar mass of glucose ( C₆H₁₂O₆ ) = 180.16 g/mol

now, { metabolizing each gram }

moles of alanine = mass taken / molar mass

= 1g / 89.09 g/mol = 1/89.09 moles

moles of glucose = mass taken / molar mass

= 1g / 180.16 g/mol = 1/180.16 moles

In each molecule of alanine, we have 3 atoms of carbon.

Also, in each molecules of glucose, we have 6 atoms of carbon

so,

number of moles of Carbons in alanine = 3 × 1/89.09 moles = 0.03367

number of moles of Carbons in glucose = 6 × 1/180.16 moles = 0.0333

so ratio of energy will be the ratio of carbon atoms, which is;

⇒ 0.03367 / 0.0333 = 1.0111

Therefore, the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose is 1.0111

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3 years ago

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Answer:

Explanation:

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2 years ago

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