All categories

4 years ago

The cell membrane that surrounds the cell acts as a _____.

Chemistry

1 answer:

kicyunya [14]4 years ago

5 0

Answer: Option B

Explanation:

Cell membrane can be defined as the outermost covering of the cell which allows the movement of particles across membrane. The particles are allowed to move from inside of the cell to the outside of the cell and from outside to inside of the cell.

This kind of a membrane is known as selectively permeable which allows the movement of certain molecules only.

hence, the correct answer is option B

You might be interested in

Which describes the letter that belongs where the question mark is?

Evgesh-ka [11]

Explanation:

Are you referring to a variable?

4 0

3 years ago

Read 2 more answers

What is the molarity of a solution that is composed of 10 grams of Sodium Chloride ( NaCl) dissolved in 3.50 L of water

Gennadij [26K]

Answer: The molarity of solution will be 0.049 M

Explanation:

Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:

$\text{Molarity of solution}=\frac{\text{Given mass of solute}}{\text{Molar mass of solute}\times \text{Volume of solution (L)}}$

We are given:

Given mass of sodium chloride = 10 g

Molar mass of sodium chloride = 58.44 g/mol

Volume of solution = 3.50 L

Putting values in above equation:

$\text{Molarity of NaCl}=\frac{10 g}{58.44g/mol\times 3.50}\\\\\text{Molarity of NaCl}=0.049M$

Hence, the molarity of solution will be 0.049 M

6 0

3 years ago

A lab scientist cools a liquid sample of water (2.6 kg) at 0.00°C to -192°C. The water turns to ice as this temperature change o

soldier1979 [14.2K]

Answer: The heat released for the given process is -1892 kJ

Explanation:

The processes involved in the given problem are:

$1.)H_2O(l)(0^oC,273K)\rightarrow H_2O(s)(0^oC,273K)\\2.)H_2O(s)(0^oC,273K)\rightarrow H_2O(s)(-192^oC,81K)$

Pressure is taken as constant.

To calculate the amount of heat released at same temperature, we use the equation:

$q=m\times L_{f,v}$ ......(1)

where,

q = amount of heat released = ?

m = mass of water/ice

$L_{f,v}$ = latent heat of fusion or vaporization

To calculate the amount of heat released at different temperature, we use the equation:

$q=m\times C_{p,m}\times (T_{2}-T_{1})$ .......(1)

where,

q = amount of heat released = ?

$C_{p,m}$ = specific heat capacity of medium

m = mass of water/ice

$T_2$ = final temperature

$T_1$ = initial temperature

Calculating the heat absorbed for each process:

For process 1:

Converting the latent heat of fusion in J/kg, we use the conversion factor:

1 kJ = 1000 J

So, $(\frac{-334kJ}{1kg})\times (\frac{1000J}{1kJ})=-334\times 10^3J/kg$

We are given:

$m=2.6kg\\L_f=-334\times 10^3J/kg$

Putting values in equation 1, we get:

$q_1=2.6kg\times (-334\times 10^3J/kg)=-868400J$

For process 2:

We are given:

$m=2.6kg\\C_{p,s}=2050J/kg.K\\T_1=273K\T_2=81K$

Putting values in equation 2, we get:

$q_2=2.6kg\times 2050J/kg.K\times (81-(273))^oC\\\\q_2=1023360J$

Total heat absorbed = $q_1+q_2$

Total heat absorbed = $[-868400+(-1023360)]J=-1891760J=-1891.76kJ\approx -1892kJ$

Hence, the heat released for the given process is -1892 kJ

3 0

3 years ago

Which formation is a result of a hot spot?

polet [3.4K]

Lol hehdjehwbjdhehsis

4 0

3 years ago

Read 2 more answers

What kinds of substances besides water can be involved in hydrogen bonding?

MrMuchimi

Kind of substance besides water:
The best example of hydrogen bonding excluding water is DNA. The two strands of polymers are connected by hydrogen bonds between the nucleotide bases.

7 0

4 years ago