Please help it’s short please!!!!!!! Thank youuuu!!!

TIMED TEST PLS HELP (will give BRAINLIEST) According to some scientists, which is a cause of global warming? PICK ONLY ONE A) de

artcher [175]

I think its c maybe im not sure

7 0

2 years ago

Read 2 more answers

Aspirin (acetylsalicylic acid, C9H8O4) is a weak monoprotic acid. To determine its acid-dissociation constant, a student dissolv

Triss [41]

Answer:

1. $3.57\times 10^{-4}$ was the $K_a$ value calculated by the student.

2. $5.93\times 10^{-4}$ was the $K_b$ of ethylamine value calculated by the student.

Explanation:

1.

The $pH$ value of Aspirin solution = 2.62

$pH=-\log[H^+]$

$[H^+]=10^{-2.62}=0.00240 M$

Moles of s asprin = $\frac{2.00 g}{180 g/mol}=0.01111 mol$

Volume of the solution = 0.600 L

The initial concentration of Aspirin = c = $\frac{0.01111 mol}{0.600 L}=0.0185 M$

$HAs\rightleftharpoons As^-+H^+$

initially

c 0 0

At equilibrium

(c-x) x x

The expression of dissociation constant :

$K_a=\frac{[As^-][H^+]}{[HAs]}$ :

$K_a=\frac{x\times x }{(c-x)}$

$=\frac{0.00240 M\times 0.00240 M}{(0.0185-0.00240 )}$

$K_a=3.57\times 10^{-4}$

$3.57\times 10^{-4}$ was the $K_a$ value calculated by the student.

2.

The $pH$ value of ethylamine = 11.87

$pH+pOH=14$

$pOH=14-11.87=2.13$

$pOH=-\log[OH^-]$

$[OH^-]=10^{-2.13}=0.00741 M$

The initial concentration of ethylamine = c = 0.100 M

$C_2H_5NH_2+H_2O\rightleftharpoons C_2H_5NH_3^{+}+OH^-$

initially

c 0 0

At equilibrium

(c-x) x x

The expression of dissociation constant :

$K_b=\frac{[C_2H_5NH_3^{+}][OH^-]}{[C_2H_5NH_2]}$ :

$K_b=\frac{x\times x}{(c-x)}$

$=\frac{0.00741\times 0.00741}{(0.100-0.00741)}$

$K_b=5.93\times 10^{-4}$

$5.93\times 10^{-4}$ was the $K_b$ of ethylamine value calculated by the student.

3 0

3 years ago

Anybody know chemistry Grahams law ?

sukhopar [10]

There is two different types but i’ll just do both meanings just incase.

Graham's Law of Diffusion: the rate of diffusion of one gas through another is inversely proportional to the square root of the density of the gas.

Graham's Law of Effusion: the rate of effusion of a gas is inversely proportional to the square root of the density of the gas.

hopes this helps..!

7 0

3 years ago

A and b are two gases that are mixed together: 2.50 mol a is mixed with 0.850 mol b. if the final pressure of the mixture is 1.7

USPshnik [31]

Partial pressure of gas A is 1.31 atm and that of gas B is 0.44 atm.

The partial pressure of a gas in a mixture can be calculated as

Pi = Xi x P

Where Pi is the partial pressure; Xi is mole fraction and P is the total pressure of the mixture.

Therefore we have Pa = Xa x P and Pb = Xb x P

Let us find Xa and Xb

Χa = mol a/ total moles = 2.50/(2.50+0.85) = 2.50/3.35 = 0.746

Xb = mol b/total moles = 0.85/(2.50+0.85) = 0.85/3.35 = 0.254

Total pressure P is given as 1.75 atm

Pa = Xa x P = 0.746 x 1.75 = 1.31atm

Partial pressure of gas A is 1.31 atm

Pb = Xb x P = 0.254 x 1.75 = 0.44atm

Partial pressure of gas B is 0.44 atm.

Learn more about Partial pressure here:

brainly.com/question/15302032

#SPJ4

6 0

2 years ago

Explain how copper conducts electricity?

gladu [14]

Answer:

Copper is a metal made up of copper atoms closely packed together. As a result, the electrons can move freely through the metal. For this reason, they are known as free electrons. They are also known as conduction electrons because they help copper be a good conductor of heat and electricity.

Explanation:

8 0

3 years ago