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4 years ago

10

You are a meteorologist measuring the changing air pressure due to an approaching weather front. What instrument would you use t

o measure atmospheric pressure?

1 answer:

posledela4 years ago

3 0

The Barometer measures the pressure while the <span>Psychrometer measures the temperature.</span>

You might be interested in

Whether a material is magnetic or not depends on what

Inessa05 [86]

It depends on what the material is.

3 0

3 years ago

Increasing the temperature of a particular liquid from 298 K to 318 K causes its vapor pressure to double. What is the enthalpy

Delvig [45]

Answer:

27.3 kJ/mol

Explanation:

Step 1: Given data

Temperature 1 (T₁): 298 K

Vapor pressure 1 (P₁): P₁

Temperature 2 (T₂): 318 K

Vapor pressure 2 (P₂): 2 P₁

Step 2: Calculate the enthalpy of vaporization of this liquid

We will use the Clausius–Clapeyron equation.

ln (P₂/P₁) = -ΔHvap/R × (1/T₂ - 1/T₁)

ln 2 = -ΔHvap/(8.314 J/K.mol) × (1/318 K - 1/298 K)

ΔHvap = 2.73 × 10⁴ J/mol = 27.3 kJ/mol

5 0

3 years ago

Many double-displacement reactions are enzyme-catalyzed via the "ping pong" mechanism, so called because the reactants appear to

zhenek [66]

Answer:

<u>D. It will decrease by a factor of 4</u>

Explanation:

According to the question , the equation follows :

$A+B\rightarrow C+D$

Rate law : This states the rate of reaction is directly proportional to concentration of reactants with each reactant raised to some power which may or may not be equal to the stoichiometeric coefficient.

$Rate\ \alpha [A]^{a}[B]^{b}$

$r=[A]^{a}[B]^{b}$ .................(1)

STEP": First, find out the power "a" and "b"

a+b = 3 (because it is given that the reaction follow 3rd order-kinetics)

According to question, <u><em>doubling the concentration of the first reactant causes the rate to increase by a factor of 2 means,</em></u>

r' = 2r if [A'] = 2[A]

Here [B] is uneffected means [B']=[B]

hence new rate =

$r'=[A']^{a}[B']^{b}$

Put the value of [A'] , [B'] and r' in the above equation:

$2r=[2A]^{a}[B]^{b}$ ...........(2)

Divide equation (1) by (2) we , get

$\frac{2r}{r}=\frac{[2A]^{2}[B]^{b}}{[A]^{a}[B]^{b}}$

$2= 2(\frac{A}{A})^{a}\times (\frac{B}{B})^{b}$

Here A and A cancel each other

B and B cancel each other

We get,

$2= 2^{a}\times 1^{b}$

1^b = 1 ( power of 1 = 1)

$2= 2^{a}$

This is possible only when a = 1

We know that : a + b = 3

1 + b = 3

b =3 -1 = 2

b = 2

Hence the rate law becomes :

$r=[A]^{a}[B]^{b}$

<u> $r=[A]^{1}[B]^{2}$ .............(3)</u>

Look in the question now, it is asked to calculate the concentration of [B],if cut in half

Hence

[B']=1/2[B]

Insert the value of [B'] in equation (3)

$r'=[A]^{1}[B']^{2}$

$r'=[A]^{1}(\frac{1}{2}[B])^{2}$

$r'=\frac{1}{4}[A]^{1}[B]^{2}$ ............(a)

But

$r=[A]^{a}[B]^{b}$ ..............(b)

Compare equation (a) and (b) , we get

new rate r' =

<u>r' = 1/4 r</u>

7 0

3 years ago

Varvara68 [4.7K]

170km/h this probs right i think

7 0

4 years ago

Which of the following liquids would have the highest viscosity at 25degC

kotykmax [81]

Answer:

Ethylene glycol

HOCH₂CH₂OH

Explanation:

For the molecules in the question, the viscosity will rise with the number of hydrogen bonds that can be formed.

A hydrogen bond is a week physical bond which is formed when hydrogen is found between atoms with high electronegativity (oxygen, nitrogen, fluorine):

O-H ··· O, N-H ··· O, N-H ··· O, O-H ··· N, F-H ··· F and so on.

Here we have have two compounds that can form hydrogen bonds (between themselves):

C) ethanol and D) ethylene glycol

Ethylene glycol have more hydroxide groups (-OH) than the ethanol so it will form more hydrogen bonds thus increasing its viscosity.

5 0

3 years ago