All categories

3 years ago

Why do water molecules and the materials dissolved in water move through the plasma membrane slowly ?

1 answer:

4 0

Nonpolar and small polar molecules can pass through the cell membrane, so they diffuse across it in response to concentration gradients. Carbon dioxide and oxygen are two molecules that undergo this simple diffusion through the membrane. The simple diffusion of water is known as osmosis.

You might be interested in

NItrogen in air reacts at high temperature to form NO2 according to the reaction:

Rina8888 [55]

Answer:

The correct answer is option E.

Explanation:

Structures for the reactants and products are given in an aimage ;

Number of double bonds in oxygen gas molecule = 1

Number of double bonds in nitro dioxide gas molecule = 1

Number of single bond in in nitro dioxide gas molecule = 1

Number of triple bonds in nitrogen gas molecule = 1

$N_2+2O_2\rightarrow 2NO_2,\Delta H=?$

$\Delta H=[2 mol\times \Delta H_{f,NO_2}]-[1 mol\times \Delta H_{f,N_2}-2 mol\times \Delta H_{f,O_2}]$

$\Delta H_{f,NO_2}=33.18 kJ/mol$

$\Delta H_{f,N_2}=0$ (pure element)

$\Delta H_{f,O_2}=0$ (pure element )

$\Delta H=2 mol\times 33.18 kJ/mol=66.36kJ=15.86 kcal$

The enthalpy of the given reaction is 15.86 kcal.

6 0

3 years ago

Study the solutions in the glasses. Put the solutions in order from concentrated to dilute.

Svetach [21]

A. 1,2,3. The solutions are getting lighter meaning the concentration is decreasing. Its most likely that water was added to dilute the solutions.

8 0

3 years ago

Four springs are stretched to the same distance from the equilibrium position. The spring constants are listed in the table. A 2

svp [43]

Answer:

The correct option is;

X, W, Y, Z

Explanation:

The parameters given are;

Spring (S), Spring Constant (N/m)

W, 24

X, 35

Y, 22

Z, 15

The equation for elastic potential energy, $E_e$ , is $E_e = 0.5 \times k \times x^2$

The above equation can also be written as $E_e =\dfrac{1}{2} \times k \times x^2$

Where:

k = The spring constant in (N/m)

x = The spring extension

Therefore, since the elastic potential energy, $E_e$ , of the spring is directly proportional to the spring constant, k, we have the springs with higher spring constant will have higher elastic potential energy, $E_e$ , therefore the correct order is as follows;

X > W > Y > Z

9 0

3 years ago

What substances were found in the innermost regions (within about the inner 0.3 au) of the solar system before planets began to

coldgirl [10]

The answer would be Rocks, metals, hydrogen compounds, hydrogen and helium, all in gaseous form.

5 0

3 years ago

Calculate the amount of heat needed to boil of benzene (), beginning from a temperature of . Be sure your answer has a unit symb

Pavlova-9 [17]

Answer:

Check explanation

Explanation:

From the question, the parameters given are 64.7g of benzene,C6H6; a starting temperature of 41.9°C and bringing it to 33.2°C.

Molar mass of benzene,C6H6= 78.11236 g/mol.

Things to know: heat capacity of benzene, C6H6= 1.63 J/g.K, the heat of fusion = 9.87 kj/mol.

STEP ONE(1): ENERGY USED IN MELTING BENZENE SOLID.

Using the formula below;

Energy used in melting the solid(in JOULES) = (mass of benzene/molar mass of benzene) × heat of Fusion.

=(64.7 g of C6H6/ 78.11236(g per mol) of C6H6) × 9.87 kJ per mol.

= 8.175 J.

= 0.008175 kJ.

STEP TWO (2): ENERGY OF HEATING THE LIQUID.

It can be calculated from the formula below;

Energy= heat capacity (J/g.K) × mass of benzene× (∆T).

= 1.63 J/g.K × 64.7 × (41.9-33.2).

= 917.5J.

= 0.9175 kJ.

Energy required to boil benzene= Energy required to melt the bezene + energy required for boiling.

= 0.008175+ 0.9175.

= 0.93kJ

Approximately, 1 kJ

8 0

3 years ago