Agar is extracted from an algae (agarophytes, <span>belong to the </span>Rhodophyta (red algae) phylum, <span>primarily from the </span>genera Gelidium<span> and </span><span>Gracilaria</span>).
Agar <span>or </span>agar-agar is a jelly-like substance. Agar is the mixture of two components, agaropectin (D-glucuronic acid and pyruvic acid) and <span>the polysaccharide agarose.</span>
Answer is: C₃H₃N₃O₃.
Chemical reaction: CₓHₓNₓOₓ + O₂ → aCO₂ + x/2H₂ + x/2N₂.
m(CₐHₓNₓ) = 5,214 g.
m(CO₂) = 5,34 g.
m(H₂) = 1,09 g.
m(N₂) = 1,70 g.
n(CO₂) = n(C) = 5,34 g ÷ 44 g/mol = 0,121 mol.
n(H₂O) = 1,09 g ÷18 g/mol = 0,06 mol.
n(H) = 2 · 0,0605 mol = 0,121 mol.
n(N₂) = 1,7 g ÷ 28 g/mol = 0,0607 mol.
n(N) = 0,0607 mol · 2 = 0,121 mol.
n(C) : n(H) : n(N) = 0,121 mol : 0,121 mol : 0,121 mol /: 0,121
n(C) : n(H) : n(N) = 1 : 1 : 1.
M(CHN) = 27 g/mol.
m(O₂) = 8,13 g - 5,214 g = 2,914 g.
n(O₂) = 2,914 g ÷ 32 g/mol = 0,09 mol.
n(CₓHₓNₓOₓ) = 5,214 g ÷ 129,1 g/mol = 0,0404 mol.
n(CₓHₓNₓOₓ) : n(CO₂) = 1 : 3.
Answer:
Vapour pressure of cyclohexane at 50°C is 490torr
Vapour pressure of benzene at 50°C is 90torr
Explanation:
Using Raoult's law, pressure of a solution is defined by the sum of the product sbetween mole fraction of both solvents and pressure of pure solvents.

In the first solution:


<em>(1)</em>
For the second equation:


<em>(2)</em>
Replacing (2) in (1):


-122.5torr = -0.250P°A

<em>Vapour pressure of cyclohexane at 50°C is 490torr</em>
And for benzene:


<em>Vapour pressure of benzene at 50°C is 90torr</em>
<h3>
Answer:</h3>
B. C7H16 + 11O2 → 7CO2 + 8H2O
<h3>
Explanation:</h3>
- In a balanced chemical equation, the number of atoms of each element is equal on both sides of the equation.
- In this case, the balanced chemical equation is;
C7H16 + 11O2 → 7CO2 + 8H2O
Because, it has 7 carbon atoms, 16 hydrogen atoms and 22 oxygen atoms on each side of the equation.
- When an equation is balanced it obeys the law of conservation of mass such that the mass of reactants will be equal to the mass of products.