All categories

3 years ago

Plzzzzzzzzzzzzzzzzzzzzzzzz help

Chemistry

2 answers:

AfilCa [17]3 years ago

8 0

Gases, bc its expand the most upon heating because the intermolecular space is more than in solids or liquids.

intermolecular space = the space between each particles

Natali5045456 [20]3 years ago

4 0

Gases

the intermolecular space between gases is more than in solids and liquid

You might be interested in

What does state of matter mean

oksano4ka [1.4K]

Answer:

If it is a solid, liquid or gas

Explanation:

5 0

3 years ago

Question 1(Multiple Choice Worth 3 points)

Bingel [31]

1) Answer:

moles of oxygen (n) = 1.86 moles

Explanation:

according to Boyle's law the formula to solve this problem is:

PV=nRt

when P is the pressure which equal 1.25 atm

and V is the volume which equal 37.5 L

n is the number of moles which we need to calculate it

R is constant which equal 0.082

t is the temperature in kelvin

By substitution:

1.25*37.5 = n * 0.082 * 307

So n = 1.86 moles

2) Answer:

the volume of oxygen gas = 34 L

Explanation:

at standard temperature and pressure (STP) 1 mole of gas will equal = 22.4L

So when we have 1.5 moles of oxygen at standard temperature and pressure (STP) so we will estimate it like that

1.5 moles *22.4 L/ 1 mole = approximately 34 L

3) Answer:

The volume of H2 = 2.29 L

Explanation:

according to the Balanced equation we can see that the molar ratio between Zn and H2 1 : 1

so to know the number of moles of H2 we will get it for Zn first :

number of moles Zn = mass of Zn / molar mass Zn

= 5.98 / 65.39 =0.0914 moles

so number of moles H2 = 0.09 moles

by substitution in the following formula:

PV = nRT

0.978 * V = 0.09 * 0.082 * 298

so The volume of H2 = 2.29 L

4) Answer:

Volume of O2 = 1.4 L

Explanation:

first we have to balance the equation:

2Na2O2 +2CO2 → 2Na2CO3 + O2

2 mole CO2 give 1 mole of O2 so the molar ratio is 2:1

at STP 1 mole of gas will equal = 22.4 L

??? moles of CO2 = 2.8

n CO2 = 0.125 moles so n O2 = 0.125 /2 = 0.0625 moles

so when 1 mole of as = 22.4

0.0625 moles O2 = ???

Volume of O2 =0.0625 moles * 22.4 L/ 1 mole

= 1.4 L

5) Answer:

the initial quantity of sodium metal used = 17.2 gram

Explanation:

at STP 1 mole of gas will equal = 22.4 L

so moles of H2 equal ?? when 8.40 liters of H2 gas were produced

so moles of H2 = 8.4/22.4 =0.375 moles

and according to the balanced equation the molar ratio between H2 ans Na is 1 : 2

so number of moles for Na = 0.375 *2 = 0.75 moles

to get the initial quantity of sodium metal (mass Na) = number of moles * molar mass

mass Na = 0.75 moles * 23 gm/mole= 17.25

6) Answer:

False

Explanation:

because STP means standard temperature and pressure. and the Standard temperature must be 273 K and the standard pressure must be 1 atm but in the question the temperature is 298 K not 273 K so , It is not a standard temperature

7) Answer:

22.4 liters

Explanation:

1 mole of gas will equal = 22.4 L

because at the Standard temperature must be 273 K and the standard pressure must be 1 atm

so V = nRT/P

=1 mole * 0.082 * 273 K / 1 aTm

= 22.4 liters

4 0

4 years ago

How many moles are in 2.4g of carbon dioxide (CO2)?

miv72 [106K]

Answer:

$\boxed {\boxed {\sf 0.055 \ mol \ CO_2}}$

Explanation:

To convert form grams to moles, the molar mass must be used. This is the mass (in grams) in 1 mole of a substance.

We can use the values on the Periodic Table. First, find the molar masses of the individual elements: carbon and oxygen.

C: 12.011 g/mol
O: 15.999 g/mol

Check for subscripts. The subscript of 2 after O means there are 2 oxygen atoms, so we have to multiply oxygen's molar mass by 2 before adding.

O₂: 2* (15.999 g/mol)=31.998 g/mol
CO₂: 12.011 g/mol + 31.998 g/mol =40.009 g/mol

Use the molar mass as a ratio.

$\frac {44.009 \ g\ CO_2}{ 1 \ mol \ CO_2}$

Multiply by the given number of grams.

$2.4 \ g \ CO_2 *\frac {44.009 \ g\ CO_2}{ 1 \ mol \ CO_2}$

Flip the fraction so the grams of carbon dioxide cancel.

$2.4 \ g \ CO_2 *\frac { 1 \ mol \ CO_2}{44.009 \ g\ CO_2}$

$2.4 *\frac { 1 \ mol \ CO_2}{44.009}$

$\frac { 2.4 \ mol \ CO_2}{44.009}= 0.0545342998 \ mol \ CO_2$

The original measurement of grams has 2 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place.

The ten thousandth place has a 5, so we round the 4 to a 5.

$0.055 \ mol \ CO_2$