This substance turns blue litmus paper red and reacts with metals to produce hydrogen gas?

The surface of water can act like a sort of skin due to a property of liquids called

dedylja [7]

Surface tension :<span>the tension of the surface film of a liquid caused by the attraction of the particles in the surface layer by the bulk of the liquid, which tends to minimize surface area.</span>

8 0

3 years ago

A solution contains 5.25 g of urea, CO(NH2)2 (a nonvolatile solute) and 0.100 kg of water. If the vapor pressure of pure water a

babymother [125]

Answer:

The vapor pressure of the solution is 23.3 torr

Explanation:

Step 1: Data given

Mass of urea = 5.25 grams

Mass of water = 0.100 kg = 100 grams

Temperature = 25.0 °C

Vapor pressure of water = 23.7 torr

Step 2: Calculate moles of water

Moles H2O = mass H2O / molar mass H2O

Moles H2O = 100 grams / 18.02 g/mol

Moles H2O = 5.55 moles

Step 3: Calculate moles of urea

Moles urea = 5.25 grams / 60.06 g/mol

Moles urea = 0.0874 moles

Step 4: Calculate mol fraction H2O

Mol fraction H2O = 5.55 moles / (5.55 + 0.0874)moles

Mol fraction H2O = 0.984

Step 5: calculate the vapor pressure of the solution

This means that you can use the mole fraction of water and the vapor pressure of pure water at 25° C to determine the vapor pressure of the solution.

Psol =Xwater * Pwater

⇒Psol = the vapor pressure of the solution

⇒Xwater =the mol fraction of water

⇒Pwater = the vapor pressure of pure water

Psol = 0.984 * 23.7 torr

Psol = 23.3 torr

The vapor pressure of the solution is 23.3 torr

3 0

4 years ago

ΔH is always positive for a ...........

scoray [572]

Answer:

a. endothermic reaction

Explanation:

In an endothermic reaction, heat is absorbed from the environment. This leaves the surrounding at a colder temperature compared to the system.

ΔH, the change in enthalpy is assigned a positive sign because the heat energy level of the final state is higher than that of the initial state.

Some examples are mostly dissolution substances in water.

8 0

3 years ago

Which one of the following is a common acid?

Assoli18 [71]

I think it’s C.Vinegar but not sure hope this helps

8 0

4 years ago

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Assuming constant pressure and temperature, how many moles of gas have been added to the initial 3 moles of gas when the volume

Temka [501]

We first assume that the gas is ideal which is a safe assumption to approximate the answer to the problem. Then we need to know the ideal gas equation and that is:

PV=nRT
where
P- pressure
V- volume
n-number of moles-
R- ideal gas constant
T-temperature.

Since we know that P, T and V are constant, rearranging the equation would lead to:

P/TR = n/V or the ratio of the moles of gas and volume is constant.

(3moles)/2L = (3+x)/4L
where
x is the additional moles.

Solving for x = 3 moles.

8 0

3 years ago

Read 2 more answers