Chemistry, 05.03.2021 17:50 snoodledoodlebop

Consider the following equation for a chemical reaction: 2H + O2 + 2H2O This can be interpreted as two molecules of hydrogen and one molecule of oxygen combining to form
two water molecules. But how often do chemists limit their reactions to one or two molecules? Usually a
reaction is done with an unimaginable number of molecules. How then do chemists know they have the
right mix? The molecules need to be quickly counted! How do we count molecules? The answer is the
unit called the mole. This activity will start by considering two egg farmers (a chicken farmer and a quail
farmer). They produce such large numbers of eggs that they can't count them all individually, so they
count in dozens of eggs in some cases, while in other cases they use mass. Weighing is often easier than
counting!
T
:
Model 1 - Eggs
Chicken
Number of eggs
Mass of the
in the sample sample
1
37.44 g
Ratio of
numbers
of eggs
Quail
Number of eggs Mass of the
in the sample
sample
1
2.34 g
10
Ratio of
masses
of eggs
1
1:1
16:1
10
438
438
61 40
1 dozen
1 dozen
1 million
1 million
1. Consider the data in Model 1.

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b is the correct answer

mark me brainliest and hope this

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They are like other investigations? say there was a murder u have to do blood test and finger prints which run through a lab.

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un recipient conține 6,4 moli de gaz. gazul hidrogen reprezintă 25% din totalul kilometrilor din container. în cazul în care presiunea totală este de 1.24 atm ceea ce este

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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

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Consider the following equation for a chemical reaction: 2H + O2 + 2H2O This can be interpreted as...

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