Answer:
9.96*10^21
Explanation:
Molar mass of K2O=29*2+16
= 74g per mol
number of moles in the sample= 1.224/ 74
=0.1654
Number of particles in 1 mole=6.0221409*10^23
Number of particles= 0.01654*6.0221409*10^23
=9.96*10^21
<span>Starch and
cellulose have the same substance but different structures. They are both
polysaccharides. The basic unit of a polysaccharide is the glucose. Glucose,
which contains carbon, hydrogen, and oxygen, have two forms. The alpha-glucose
with an alcohol group attached to carbon 1 is down and the beta-glucose with
the alcohol group attached to carbon 1 is up. Starch is the alpha-glucose while
cellulose is the beta-glucose. Starches are linked into a straight chain whereas
the cellulose are connected like a pile of stack paper. When the human body
eats starch, it can digest the starch but not the cellulose because it has no
enzyme that can break it down. </span>
Answer:
Final temperature of the gas is 576 
.
Explanation:
As the amount of gas and pressure of the gas remains constant therefore in accordance with Charles's law:
where 
and 
are volume of gas at 
and 
temperature (in kelvin scale) respectively.
Here 
, 
and 
So 
849 K = (849-273) = 576
So final temperature of the gas is 576 .
Answer:
55.3 × 10²³ molecules
Explanation:
Given data:
Number of moles of C₁₁H₁₂O₂₂ = 9.18 mol
Number of molecules = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
For given data:
9.18 mol × 6.022 × 10²³ molecules /1 mol
55.3 × 10²³ molecules
Answer:
Explanation:
The given pH = 8.55
Unknown:
[H₃O⁺] = ?
[OH⁻] = ?
In order to find these unknowns we must first establish some relationship.
pH = -log[H₃O⁺]
8.55 = -log[H₃O⁺]
[H₃O⁺] = inverse log₁₀(-8.55) = 2.82 x 10⁻⁹moldm⁻³
To find the [OH⁻],
pH + pOH = 14
pOH = 14 - pH = 14 - 8.55
pOH = 5.45
pOH = -log[OH⁻]
[OH⁻] = inverse log₁₀ (-5.45) = 3.55 x 10⁻⁶moldm⁻³
The solution is basic because it has more concentration of OH⁻ ions compared to H⁺ ions.
