Chemistry, 09.02.2021 18:30 henriquetucker

Below is a structural equation for the combustion of methane gas (CH4): H
1
С
+ 0 = 0
O = C =0
HOH HOH
1
O = 0
2a) Using the information in the combustion reaction above and the bond energy values in the table below
Bond
H-H
C-H
0=0
O-H
C=0
C-C
436
413
496
463
743
346
Bond energy
(kJ/mol)
Calculate:
Bonds broken (reactants)
Bonds made (products)

Answers: 3

Show answers

Answers

Answer from: Quest

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation:

What do lines on a contour map indicate?

Answer from: Quest

Rn in the right answer

Answer from: Quest

Atp, shorthand for adenosine triphosphate, is the standard molecule for cellular enger in the human body. all motion and metabolic processes within the body begins with energy that is released from atp, as its phosphate bonds are broken in cells through a process called hydrolysis.

Answer from: Quest

the missing options are :

(1) lower boiling point and a lower freezing point(2) lower boiling point and a higher freezing point(3) higher boiling point and a lower freezing point(4) higher boiling point and a higher freezing point

answer : the correct answer is option (3) higher boiling point and a lower freezing point

explanation :

when a non volatile solute is added to a solvent like water, it results in elevation of boiling point.

let us find the increase in boiling point of water when cacl₂ is added to water to make a solution of 1 m

step 1 : find molality of the solution

let us assume we have 1 l of solution.

$m = \frac{moles (solute)}{l ( solution)}$

$1 m = \frac{moles (cacl_{2})}{1 l }= 1 mol cacl_{2}$

let us convert this to grams of cacl₂.

molar mass of cacl2 is 111 g/mol

grams of cacl₂ = $1 mol \times \frac{111g}{mol} = 111 g cacl_{2}$

mass of solute = 111 g

assuming density of solution same as water which is 1g/ml we have ,

mass of solution = density * volume

mass of solution = $\frac{1g}{ml} \times 1000 ml = 1000 g$

mass of solution = mass of solvent + mass of solute

mass of solute = 1000g - 111g

mass of solute 889 g = 0.889 kg

the molality of the solution can be calculated as

$molality = \frac{mol (solute)}{kg ( solvent)}$

$molality = \frac{1mol}{0.889kg}$

molality = 1.12 m

step 2 : find boiling point elevation.

the elevation in boiling point is calculated as

$\bigtriangleup t_{b} = i \times k_{b} \times m$

here δtb = boiling point elevation

i = vant hoff factor which is the number of ions formed by the solute .

cacl₂ dissociates as $cacl_{2} \rightarrow ca^{2+} + 2 cl^{-}$

it forms 3 ions . therefore,

i = 3

m = molality which is 1.12 m

kb is constant for a given solvent. for water it is 0.512

$\bigtriangleup t_{b} = 3 \times 0.512 \times 1.12$

$\bigtriangleup t_{b} = 1.7$

the boiling point of water increases by 1.7 °c

step 3: find freezing point depression.

when a non volatile solute is added to water, it results in decrease in freezing point.

the formula to find freezing point depression is

$\bigtriangleup t_{f} = i \times k_{f} \times m$

kf is constant for water and its value is 1.86

$\bigtriangleup t_{f} = 3 \times 1.86 \times 1.12$

$\bigtriangleup t_{f} = 6.2$

the freezing point of water decreases by 6.2 °c

therefore we can say that, the solution will have a higher boiling point and a lower freezing point

Another question on Chemistry

Chemistry, 22.06.2019 11:40

Consider this equilibrium: n29) + o2(g) + 2no(c).nitrogen gas and oxygen gas react when placed in a closed container. as the reaction proceeds towards equilibrium, what happens to the rate of thereverse reaction?

Answers: 1

Answer

Chemistry, 22.06.2019 18:20

Which reason best explains why metals are malleable? a)because they have delocalized electrons b)because they have localized electrons c)because they have ionic bonds d)because they have rigid bonds

Answers: 2

Answer

Chemistry, 22.06.2019 21:00

One similarity and one difference between an element and a mixture of elements

Answers: 1

Answer

Chemistry, 22.06.2019 23:00

Need asap question 1 minerals are organic compounds. true false question 2 what vitamin can be found in foods like oranges, grapefruits, and broccoli? a. vitamin a b. vitamin k c.vitamin c d. vitamin d question 3 what are minerals? a. chemical elements that are needed for body processes. b. organic compounds that the body needs in small amounts to function properly. c. small molecules used to build proteins. d. an organic compound that is insoluble in water and includes fats. question 4 how many types of vitamins does the human body need? a. 15 b. 11 c. 13 d. 17 question 5 vitamins are a good source of energy. true false

Answers: 1

Answer

You know the right answer?

Below is a structural equation for the combustion of methane gas (CH4): H
1
С
+ 0 =...

Questions