Answer:
PV=nRt
Therefore n(number of moles)=PV/RT
=>(0.49×3.80)/(0.08206×320)
Therefore Number of moles is = 0.071mols
Explanation: By using the Real gas equation..
PV=NRT .
We can solve for the number of moles of Ar by making N the subject..
Always make sure you pressure is In atm, your Volume is in Litres and temperature in degree Kelvin.
Also Recall the universal gas constant R used in this type of questions which is 0.08206.
Hence l, by making N the subject we get our answer as
An example of accurate but not precise would be 3 people weigh a 10g sample. the weights are 0g, 10g, & 20 grams. the scale is way off but the weights average to the right thing.
precise but not accurate would weighing a 10g sample 3 times and getting 5.5, 5.4, & 5.5. they'e all incredibly similar therefore precise but its nowhere near 10, so not accurate.
neither precise nor accurate would be 3 weights being 10, 20, &30. It averages wrong and is imprecise.
Answer:
There are two types of hydrocarbons: aliphatic and aromatic. The three types of aliphatic hydrocarbons are alkanes, alkenes, and alkynes. Aromatic hydrocarbons include benzene. Overall, examples of hydrocarbons are methane, ethane, propane, and butane.
A. phase changing. Physical change is any change in matter that involves the substance going from one physical state to another, and phase change is most commonly used to describe transitions between solid, liquid and gaseous states of matter.
In one mole of C7H18 there are 18 moles of H (the number folowing the H)*
>> the ratio is 1:18
In 5.2 moles of C7H18 there are x moles of H
>> the ratio is 5.2:x
Cross multiply the two ratios
1x = 18×5.2
x = 93.6 moles of H
>> In 5.2 moles of C7H18 there are 93.6 moles of H
* This isnt a rule that you can always use.
However to find the mole of a certain element in a certain molucle all you have to do is count how many moles of the element are present in the molecule.
>> example1 >> H2O ;
2 H and 1 O
>> example2 >> CH3COOH ; [you add up all the moles of the same element]
(1+1) 2 C , (3+1) 4 H and (1+1) 2 O
>> example3 >> Mg(OH)2 ; [you multiply whetever is in parenthesis by the number after it 2] 1 Mg , (1×2) 2 O and (1×2) 2 H
