What is the pH of a neutral solution at 25°C? 7 1

The pressure on 150 mL of a gas is increased from 500 mm Hg to 700 mm Hg at constant temperature. What is the new volume of the

Ivanshal [37]

Answer:

Option A. 107 mL

Explanation:

From the question given above, the following data were obtained:

Initial volume (V₁) = 150 mL

Initial pressure (P₁) = 500 mmHg

Final pressure (P₂) = 700 mmHg

Temperature = constant

Final volume (V₂) =?

The final volume of the gas can be obtained by using the Boyle's law equation as shown below:

P₁V₁ = P₂V₂

500 × 150 = 700 × V₂

75000 = 700 × V₂

Divide both side by 700

V₂ = 75000 / 700

V₂ = 107 mL

Therefore, the final volume of the gas is 107 mL.

4 0

3 years ago

A solution is made by dissolving 4.87 g of potassium nitrate in water to a final volume of 86.4 mL solution. What is the weight/

lara31 [8.8K]

Answer:

A solution is made by dissolving 4.87 g of potassium nitrate in water to a final volume of 86.4 mL solution. The weight/weight % or percent by mass of the solute is :

2.67%

Explanation:

Note : Look at the density of potassium nitrate in water if given in the question.

You are calculating weight /Volume not weight/weight % or percent by mass of the solute

Here the weight/weight % or percent by mass of the solute is asked : So first convert the VOLUME OF SOLUTION into MASS

Density of potassium nitrate in water KNO3 = 2.11 g/mL

$density=\frac{mass}{volume}$

Density = 2.11 g/mL

Volume of solution = 86.4 mL

$2.11=\frac{mass}{86.4}$

$mass = 2.11\times 86.4$

$mass=182.3grams$

Mass of Solute = 4.87 g

Mass of Solution = 183.2 g

w/w% of the solute =

$= \frac{mass\ of\ solute}{mass\ of\ solution}\times 100$

$=\frac{4.87}{183.2}\times 100$

w/w%=2.67%

8 0

3 years ago

Light, heat, and ultraviolet radiation are types of ___ produces by stars

Charra [1.4K]

Answer:

energy

Explanation:

Those are all forms of energy

6 0

3 years ago

Carvone (C10H14O) is the main component of spearmint oil. It has a pleasant aroma and mint flavor. Carvone is often added to che

marta [7]

Answer: The mass of carbon in given amount of carvone is 47.52 grams

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

Given mass of carvone = 55.4 g

Molar mass of carvone = 150.22 g/mol

Putting values in equation 1, we get:

$\text{Moles of carvone}=\frac{55.4g}{150.22g/mol}=0.369mol$

The chemical formula of carvone is $C_{10}H_{14}O$

This contains 10 moles of carbon atom, 14 moles of hydrogen atom and 1 mole of oxygen atom

Now, calculating the mass of carbon in carvone from equation 1, we get:

Molar mass of carbon = 12 g/mol

Moles of carbon = (10 × 0.396) = 3.96 moles

Putting values in equation 1, we get:

$3.96mol=\frac{\text{Mass of carbon}}{12g/mol}\\\\\text{Mass of carbon}=(3.96mol\times 12g/mol)=47.52g$

Hence, the mass of carbon in given amount of carvone is 47.52 grams

6 0

3 years ago

How many grams of mercury would be contained in 15 compact fluorescent light bulbs?

zhenek [66]

Answer:

Grams of mercury= 0.06 g of Hg

Note: The question is incomplete. The complete question is as follows:

A compact fluorescent light bulb contains 4 mg of mercury. How many grams of mercury would be contained in 15 compact fluorescent light bulbs?

Explanation:

Since one fluorescent light bulb contains 4 mg of mercury,

15 such bulbs will contain 15 * 4 mg of mercury = 60 mg

1 mg = 0.001 g

Therefore, 60 mg = 0.001 g * 60 = 0.06 g of mercury.

Compact fluorescent lightbulbs (CFLs) are tubes containing mercury and noble gases. When electricity is passed through the bulb, electron-streams flow from a tungsten-coated coil. They collide with mercury atoms, exciting their electrons and creating flashes of ultraviolet light. A phosphor coating on the inside of the tube absorbs this UV light flashes and re-emits it as visible light. The amount of mercury in a fluorescent lamp varies from 3 to 46 mg, depending on lamp size and age.

5 0

3 years ago