What type of change is the process of solid ice changing into liquid water?

Explain, in terms of energy, why the temperature of the reaction mixture increases

Dima020 [189]

Answer:

Magnesium reacts with dilute hydrochloric acid in a conical flask which is connected to an inverted measuring cylinder in a trough of water. The volume of hydrogen gas produced is measured over a few minutes, and the results are used to plot a graph........

8 0

2 years ago

A coffee-cup calorimeter initially contains 125 g water at 24.28C. Potassium bromide (10.5 g), also at 24.28C, is added to the w

iren2701 [21]

Answer:

The solution is given below

Explanation:

Heat, q= mc∆T

q= 125g x 4.18 J/g∙°C x (21.18x- 24.28) °C

q= -1619.75J

NEGATIVE SIGN INDICATES THAT HEAT IS ABSORBED.

Enthalpy Change, ∆H = 1619.75 7/ 10.5 g

= 154.26 J/g

No. of moles of KBr = Mass of KBr/ Molecular Weight of KBr

=10.5g/119gmol-1

=0.088 mol

∆H= 1619.75 J/ 0.088 mol

= 18.41 kJ/mol

6 0

3 years ago

Problem PageQuestionSteam reforming of methane ( ) produces "synthesis gas," a mixture of carbon monoxide gas and hydrogen gas,

Serhud [2]

The question is incomplete. Her eis the complete question.

Steam reforming methane (CH4) produces "synthesis gas", a mixture of carbon monoxide gas and hydrogen gas, which is the starting point for many important industrial chemical syntheses. An industrial chemist studying this reaction fills a 125L tank with 20 mol of methane gas and 10 mol of water vapor at 38°C. He then raises the temperature, and when the mixture has come to equilibrium measures the amount of gas hydrogen to be 18 mol. Calculate the concentration equilibrium constant for the steam reforming of methane at the final temperature of the mixture. Round your answer to significant digits.

Answer: $K_{c}$ = 2. $10^{-2}$

Explanation: The reaction for steam reforming methane is:

$CH_{4} + H_{2}O$ ⇒ $CO_{} + 3H_{2}$

To calculate the concentration equilibrium constant, first calculate the molarity ( $\frac{mol}{L}$ ) of each molecule of the reaction.

At 38°C: At the initial temperature, there no products yet

Molarity of CH4:

CH4 = $\frac{20}{125}$ = 0.16M

Molarity of H20:

H2O = $\frac{10}{125}$ = 0.08M

At final temperature:

Molarity of H2:

H2 = $\frac{18}{125}$ = 0.144M

According to the chemical reaction, the combination of 1 mol of each reagents produces 1 mol of CO and 3 mols of H2, so, for the products, the ratio is 1:3.

Molarity of CO:

CO = $\frac{0.144}{3}$ = 0.048M

For the reagents, the proportion is 1:1, but they had an initial concentration, so, when in equilibrium, the concentration will be:

Molarity of CH4:

CH4 = 0.16 - 0.048 = 0.112M

Molarity of H2O:

H20 = 0.08 - 0.048 = 0.032M

The equilibrium constant is given by:

$K_{c} = \frac{[CO][H_{2}]^{3} }{[CH_{4}][H_{2}O ] }$

$K_{c}$ = $\frac{0.048.0.144^{3} }{0.112.0.032}$

$K_{c}$ = 2. $10^{-2}$

The concentration equilibrium constant for the process is $K_{c}$ = 2. $10^{-2}$ .

4 0

3 years ago

Nitrogen ion (Nitride) is ... Cation/Anion/Neither? # of protons? # of electrons? Charge (1-, 2-, 3-, 1+, 2+, 3+, or 0) Number o

OLga [1]

Answer:

3- is the charge and 8 dots on its Lewis dot structure.

Explanation:

Hello there!

In this case, since nitrogen is an element with five valence electrons (electrons on its outer shell), we infer that it needs three bonds to complete the octet, for which its charge, when forming nitride ions is 3-, which means it has received three electrons. Thus, when drawing the Lewis dot structure, it is evident that is will have 5+3 = 8 dots due to the electron reception.

Regards!

8 0

2 years ago

How is volume calculated given mass and density

Ymorist [56]

Answer:

volume is equal to the mass divided by the density (V = M/d).

4 0

2 years ago

Read 2 more answers