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3 years ago

A 4-g mass of NaOH is dissolved in 5mL of water.

1 answer:

6 0

Molar mass NaOH = 40.0 g/mol

Volume in liters of solution :

5 mL / 1000 => 0.005 L

number of moles :

4 / 40 => 0.1 moles

M = n / V

M = 0.1 / 0.005

= 20 mol/L or 20 M

hope this helps!

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A 3.06 gram sample of an unknown hydrocarbon with empirical formula CH2O was found to contain 0.0170 moles of the substance. Wha

Yanka [14]

Answer:

180 amu

C₆H₁₂O₆

Explanation:

Step 1: Determine the molecular mass of the compound

The sample has a mass (m) of 3.06 g and it contains (n) 0.0170 moles. The molar mass M is:

M = m/n = 3.06/0.0170 mol = 180 g/mol

Then, the molecular mass is 180 amu.

Step 2: Determine the molar mass of the empirical formula.

M(CH₂O) = 1 × M(C) + 2 × M(H) + 1 × M(O)

M(CH₂O) = 1 × 12 g/mol + 2 × 1 g/mol + 1 × 16 g/mol = 30 g/mol

Step 3: Determine the molecular formula

First, we will determine "n" according to the following expression.

n = molar mass molecular formula / molar mass empirical formula

n = 180 g/mol / 30 g/mol = 6

The molecular formula is:

n × CH₂O = 6 × CH₂O = C₆H₁₂O₆

5 0

3 years ago

What is the biological significance of the temperature at which the amylase catalyzed reaction

ipn [44]

Answer:

The biological significance is that it is the normal human body temperature and also the optimum temperature of the enzyme.

Explanation:

Enzymes are biological catalysts that speed up the rate of chemical reactions.
Enzymes catalyze specific reactions by working on a specific substrate to convert it into a product.
The rate of enzyme activity depends on several factors which include pH, temperature, substrate concentration, and enzyme concentration among others.
Enzymes work best at a specific pH and temperature known as optimum pH and optimum temperature respectively.
In this case, enzyme amylase works best at a temperature of 37° C which is equivalent to the normal human body temperature.

7 0

3 years ago

Which graph correctly shows the effect on the freezing point caused by increasing the molality of a solution ?

beks73 [17]

The answer to your question is graph A :)

6 0

3 years ago

Read 2 more answers

12.70 L of a gas has a pressure of 0.63 atm. What is the volume of the gas at 105kPa?

Zielflug [23.3K]

Answer: 7.693 L

Explanation:

To calculate the new volume, we use the equation given by Boyle's law. This law states that pressure is directly proportional to the volume of the gas at constant temperature.

The equation given by this law is:

$P_1V_1=P_2V_2$

where,

$P_1\text{ and }V_1$ are initial pressure and volume.

$P_2\text{ and }V_2$ are final pressure and volume.

We are given:

$P_1=0.63atm\\V_1=12.70L\\P_2=105kPa=1.04atm(1kPa=0.009atm)\\V_2=?$

Putting values in above equation, we get:

$0.63\times 12.70mL=1.04\times V_2\\\\V_2=7.693L$

Thus new volume of the gas is 7.693 L

6 0

3 years ago

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In your own words, what do you think an atom is?

Lelu [443]

Answer:

An atom is a particle of matter that uniquely defines achemical element. An atom consists of a central nucleus that is usually surrounded by one or more electrons. Each electron is negatively charged. The nucleus is positively charged, and contains one or more relatively heavy particles known as protons and neutrons.

5 0

3 years ago