All categories

3 years ago

73.5 grams C, 4.20 grams H, and 72.3 grams Cl. What is the percent composition of each element in this compound?

1 answer:

6 0

To find percent composition do "parts over the whole" ---> each individual mass over the total mass times 100 (since it is a percentage).

total mass ("the whole")= 73.5 + 42.0 + 72.3 grams= 150 grams

1. Carbon %= 73.5 grams/ 150 grams x 100= 49.0%

2. Hydrogen %= 4.20 grams/ 150 grams x 100= 2.80%

3. Chlorine %= 72.3 grams/ 150 grams x 100= 48.2%

You might be interested in

On a cool morning, uyen’s breath can form a cloud when she breathes out. which changes of state are most responsible for uyen se

Ganezh [65]

<span>You may already know that when you breathe in, your body takes in oxygen from the air. When you breathe out, your lungs expel carbon dioxide back into the air. But the breath you breathe out contains more than just carbon dioxide.</span>

When you exhale (breathe out), your breath also containsmoisture. Because your mouth and lungs are moist, each breath you exhale contains a little bit of water in the form of water vapor(the gas form of water).

For water to stay a gas in the form of water vapor, it needs enough energy to keep its molecules moving. Inside your lungs where it's nice and warm, this isn't a problem.

4 0

3 years ago

Read 2 more answers

What is the density of an object having a volume of 8 ml and a mass of 22 grams?

solniwko [45]

Answer:

0.32gcm3 . I miss the old Kanye, straight from the 'Go Kanye

Chop up the soul Kanye, set on his goals Kanye

I hate the new Kanye, the bad mood Kanye

The always rude Kanye, spaz in the news Kanye

I miss the sweet Kanye, chop up the beats Kanye

I gotta to say at that time I'd like to meet Kanye

See I invented Kanye, it wasn't any Kanyes

And now I look and look around and there's so many Kanyes

I used to love Kanye, I used to love Kanye

I even had the pink polo, I thought I was Kanye

What if Kanye made a song about Kanye

Called "I Miss The Old Kanye, " man that would be so Kanye

That's all it was Kanye, we still love Kanye

And I love you like Kanye loves Kanye

Explanation:

5 0

2 years ago

Read 2 more answers

Does potassium nitrate (KN03) incorporate ionic bonding, covalent bonding, or both? Explain.

ladessa [460]

Answer: $KNO_3$ incorporates both ionic bonding and covalent bonding.

Explanation:

A covalent bond is formed when an element shares its valence electron with another element. This bond is formed between two non metals.

An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and the element which accepts the electrons is known as electronegative element. This bond is formed between a metal and an non-metal.

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

Here potassium is having an oxidation state of +1 called as $K^{+}$ cation and nitrate $NO_3^{-}$ is an anion with oxidation state of -1. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral $KNO_3$ . $NO_3^-$ is formed by sharing of electrons between two non metals nitrogen and oxygen.

Thus $KNO_3$ incorporates both ionic bonding and covalent bonding.

4 0

3 years ago

Be sure to answer all parts. Styrene is produced by catalytic dehydrogenation of ethylbenzene at high temperature in the presenc

svlad2 [7]

Answer:

a) ΔHºrxn = 116.3 kJ, ΔGºrxn = 82.8 kJ, ΔSºrxn = 0.113 kJ/K

b) At 753.55 ºC or higher

c )ΔG = 1.8 x 10⁴ J

K = 8.2 x 10⁻²

Explanation:

a) C6H5−CH2CH3 ⇒ C6H5−CH=CH2 + H₂

ΔHf kJ/mol -12.5 103.8 0

ΔGºf kJ/K 119.7 202.5 0

Sº J/mol 255 238 130.6*

Note: This value was not given in our question, but is necessary and can be found in standard handbooks.

Using Hess law to calculate ΔHºrxn we have

ΔHºrxn = ΔHfº C6H5−CH=CH2 + ΔHfº H₂ - ΔHºfC6H5−CH2CH3

ΔHºrxn = 103.8 kJ + 0 kJ - (-12.5 kJ)

ΔHºrxn = 116.3 kJ

Similarly,

ΔGrxn = ΔGºf C6H5−CH=CH2 + ΔGºfH₂ - ΔGºfC6H5CH2CH3

ΔGºrxn= 202.5 kJ + 0 kJ - 119.7 kJ = 82.8 kJ

ΔSºrxn = 238 J/mol + 130.6 J/mol -255 J/K = 113.6 J/K = 0.113 kJ/K

b) The temperature at which the reaction is spontaneous or feasible occurs when ΔG becomes negative and using

ΔGrxn = ΔHrxn -TΔS

we see that will happen when the term TΔS becomes greater than ΔHrxn since ΔS is positive , and so to sollve for T we will make ΔGrxn equal to zero and solve for T. Notice here we will make the assumption that ΔºHrxn and ΔSºrxn remain constant at the higher temperature and will equal the values previously calculated for them. Although this assumption is not entirely correct, it can be used.

0 = 116 kJ -T (0.113 kJ/K)

T = 1026.5 K = (1026.55 - 273 ) ºC = 753.55 ºC

c) Again we will use

ΔGrxn = ΔHrxn -TΔS

to calculate ΔGrxn with the assumption that ΔHº and ΔSºremain constant.

ΔG = 116.3 kJ - (600+273 K) x 0.113 kJ/K = 116.3 kJ - 873 K x 0.113 kJ/K

ΔG = 116.3 kJ - 98.6 kJ = 17.65 kJ = 1.8 x 10⁴ J ( Note the kJ are converted to J to necessary for the next part of the problem )

Now for solving for K, the equation to use is

ΔG = -RTlnK and solve for K

- ΔG / RT = lnK ∴ K = exp (- ΔG / RT)

K = exp ( - 1.8 x 10⁴ J /( 8.314 J/K x 873 K)) = 8.2 x 10⁻²

8 0

3 years ago

Are protons and neutrons the same size? Explain.

Ivahew [28]

no because they are two diffrent things

4 0

3 years ago