Which agents cause both chemical and physical weathering?

Four grams of magnesium react with an excess of dilute hydrochloric acid. Calculate the volume in liters of hydrogen gas collect

Helga [31]

Sorry I am confuse 3

5 0

3 years ago

Part a use these data to calculate the heat of hydrogenation of buta-1,3-diene to butane. c4h6(g)+2h2(g)→c4h10(g)

Reptile [31]

<u>Answer:</u> The heat of hydrogenation of the reaction is coming out to be 234.2 kJ.

<u>Explanation:</u>

Enthalpy change is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles. It is represented as $\Delta H$

The equation used to calculate enthalpy change is of a reaction is:

$\Delta H_{rxn}=\sum [n\times \Delta H_{(product)}]-\sum [n\times \Delta H_{(reactant)}]$

For the given chemical reaction:

$C_4H_6(g)+2H_2(g)\rightarrow C_4H_{10}(g)$

The equation for the enthalpy change of the above reaction is:

$\Delta H_{rxn}=[(1\times \Delta H_{(C_4H_{10})})]-[(1\times \Delta H_{(C_4H_6)})+(2\times \Delta H_{(H_2)})]$

We are given:

$\Delta H_{(C_4H_{10})}=-2877.6kJ/mol\\\Delta H_{(C_4H_6)}=-2540.2kJ/mol\\\Delta H_{(H_2)}=-285.8kJ/mol$

Putting values in above equation, we get:

$\Delta H_{rxn}=[(1\times (-2877.6))]-[(1\times (-2540.2))+(2\times (-285.8))]\\\\\Delta H_{rxn}=234.2J$

Hence, the heat of hydrogenation of the reaction is coming out to be 234.2 kJ.

4 0

3 years ago

1. Ibuprofen (C13H18O2) is the active ingredient in many nonprescription pain relievers. Each tablet contains 200 mg of ibuprofe

Dmitry_Shevchenko [17]

Answer :

The molar mass of ibuprofen is, 206.29 g/mole.

The number of moles of ibuprofen in a single tablet is, 0.000969 moles

The number of moles of ibuprofen in four doses is, 0.007752 moles

Solution : Given,

Molar mass of carbon = 12.01 g/mole

Molar mass of hydrogen = 1.01 g/mole

Molar mass of oxygen = 15.99 g/mole

1) Now we have to calculate the molar mass of ibuprofen.

Molar mass of ibuprofen, $C_{13}H_{18}O_2$ = $(13\times 12.01)+(18\times 1.01)+(2\times 15.99)=206.29g/mole$

The molar mass of ibuprofen = 206.29 g/mole

2) Now we have to calculate the moles of ibuprofen.

Formula used : $Moles=\frac{Mass}{\text{ Molar mass}}$

Given : Mass of ibuprofen = 200 mg = 0.2 g (1 mg = 1000 g)

$\text{ Moles of ibuprofen}=\frac{\text{ Mass of ibuprofen}}{\text{ Molar mass of ibuprofen}}=\frac{0.2g}{206.29g/mole}=0.000969moles$

The moles of ibuprofen = 0.000969 moles

3) Now we have to calculate the number of moles of ibuprofen for four doses.

Number of tablets in one dose = 2

Total number of tablets in 4 doses = 4 × 2 = 8

Number of moles of ibuprofen in 8 tablets =

$\text{ Number of moles of ibuprofen in 1 tablet}\times \text{ Total number of tablets}=0.000969\times 8=0.007752moles$

6 0

3 years ago

Read 2 more answers

HELP PLEASE!! (100 points)

MrRa [10]

Answer:

As you cool a matter to absolute zero, their kinetic energy reduces significantly and the molecules slows down and begins to aggregate together. ... As heat is added, the molecules gain more kinetic energy. This shown in their increase motion. When heat is withdrawn, the particles slows down hope this helped

3 0

2 years ago

HELP ASAP I will give you a brainliest

mixer [17]

Answer: its the first one buster

3 0

2 years ago