According to the graph, which statement is true?

As ________________ increases, air pressure decreases. A) pollution B) water vapor C) radiation D) altitude

lara [203]

Answer:

d or b

Explanation:

8 0

3 years ago

Choose the statement that best describes the effects of a higher or lower pH on enzymes.

matrenka [14]

<h3>Answer:</h3>

Higher or lower pH affect the structure of the enzyme and reduces the enzyme activity.

<h3>Explanation:</h3>

Enzymes are biological molecules that speed up the rate of chemical reactions.
Enzyme activity is affected by several factors which include temperature, pH, and enzyme inhibitors.
Enzymes work on specific molecules known as substrates. They are substrate-specific.
Enzymes work best at optimum pH and temperature.
Higher or lower pH affects the structure and charges of an enzyme thus affecting enzyme activity.
Lower temperature deactivates the enzymes while higher temperatures denature the enzymes.

8 0

3 years ago

Suppose a layer of oil is on the top of a beaker of water. Water in many oils is slightly soluble, so its concentration is so lo

rodikova [14]

Explanation:

It is given that energy to transfer one water molecule is $2.208 \times 10^{-20}$ J/molecule

As it is known that in 1 mole there are $6.022 \times 10^{23}$ atoms.

So, energy in 1 mole = $2.208 \times 10^{-20} \times 6.022 \times 10^{23}$ J/mol

= 13.3 kJ/mol

As, $log \frac{k_{2}}{k_{1}} = \frac{E_{a}}{2.303 \times 8.314 atm L/mol K} \times \frac{T_{2} - T_{1}}{T_{1}T_{2}}$

Putting the given values in the above formula as follows.

$log \frac{k_{2}}{k_{1}} = \frac{E_{a}}{2.303 \times 8.314 atm L/mol K} \times \frac{T_{2} - T_{1}}{T_{1}T_{2}}$

$log \frac{k_{2}}{k_{1}} = \frac{13.3 kJ/mol}{2.303 \times 8.314 atm L/mol K} \times \frac{293 K - 283 K}{283K \times 293 K}$

$log \frac{k_{2}}{k_{1}}$ = 0.08377

$\frac{k_{2}}{k_{1}}$ = 1.213 = $\frac{Concentration_{2}}{Concentration_{1}}$

$Concentration_{2}$ = $1.213 \times Concentration_{1}$

= $1.213 \times 9 \times 10^{-4}$

= $10.915 \times 10^{-4}$ water molecules per oil molecule

Thus, we can conclude that the equilibrium concentration at 293 K, assuming that nothing else changes is $10.915 \times 10^{-4}$ .

4 0

3 years ago

How many moles of Calcium are in a sample of 40g?

NeTakaya

<span>40 grams ÷ 40.08 grams/moles = 1 mole</span>

5 0

3 years ago

When 8.70 kJ of thermal energy is added to 2.50 mol of liquid methanol, it vaporizes. Determine the heat of vaporization in kJ/m

andreev551 [17]

Answer:

The heat of vaporization in kJ/mol of methanol

= 3.48 kJ/mole

Explanation:

Here,the heat of vaporization in kJ/mol is asked to calculate.<em><u>This means it is asked to calculate heat required for 1 mole of methanol.</u></em> Since the substance<em> vaporizes </em>, so this is called <u>heat of vaporization.</u>

Divide the thermal energy with the number of moles .

This is simple mathematics :

If 2.50 mol of liquid require = 8.70 kJ of energy

Then, 1 mole will need =

$\frac{8.70}{2.50}$

= 3.48 kJ/mole

<em><u>Follow the units :</u></em>

The heat of vaporization in kJ/mol of methanol is asked.

$Heat\ of\ Vaporization=\frac{Thermal\ energy}{Moles}$

$=\frac{kJ}{mole}$

Unit = kJ /Mole

3 0

3 years ago