Answer:
C₄H₈O₂.
Explanation:
- Firstly, we can calculate the no. of moles (n) of each component using the relation:
<em>n = mass/atomic mass,</em>
mol C = mass/(atomic mass) = (54.5 g)/(12.0 g/mol) = 4.54 mol.
mol H = mass/(atomic mass) = (9.3 g)/(1.0 g/mol) = 9.3 mol.
mol O = mass/(atomic mass) = (36.2 g)/(16.0 g/mol) = 2.26 mol.
- To get the empirical formula, we divide by the lowest no. of moles (2.26 mol) of O:
∴ C: H: O = (4.54 mol/2.26 mol) : (9.3 mol/2.26 mol) : (2.26 mol/2.26 mol) = 2: 4: 1.
<em>∴ Empirical formula mass of (C₂H₄O) = 2(atomic mass of C) + 4(atomic mass of H) + 1(atomic mass of O) =</em> 2(12.0 g/mol) + 4(1.0 g/mol) + (16.0 g/mol)<em> = 44.0 g/mol.</em>
∴ Number of times empirical mass goes into molecular mass = (88.0 g/mol)/(44.0 g/mol) = 2.0 times.
∴ The molecular formula is, 2(C₂H₄O), that is; <em>(C₄H₈O₂)</em>
Answer:
The change of state of wax from solid to liquid and liquid to vapors is a physical change.
Explanation:
Physical Change
The changes that occur only due to change in shape or form but their chemical or internal composition remain unchanged.
These changes were reversible.
They have same chemical property.
These changes can be observed with naked eye.
Chemical:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
These changes are irreversible
.
These changes occur due to chemical reactions.
These may not be observed with naked eye
Example
When a candle is burned, the both physical and chemical changes occur.
The solid wax is melted into the liquid and than liquid is evaporated into vapor form. It is a physical change because just the state of mater is changed. When vapors of wax are react with oxygen in air and form carbon dioxide and ash it is a chemical change which can not be reversed.
I believe the scientific method
Answer:
the soup become too salty through the process of osmosis
Answer:
0.425M NaOH assuming the volume of KHP was 25.50mL and the volume of the NaOH solution was 30.0mL
Explanation:
The KHP reacts with NaOH as follows:
KHP + NaOH → KNaP + H₂O
<em>Where 1 mole of KHP reacts per mole of KNaP</em>
<em />
That means, the moles of KHP added to the NaOH solution = Moles NaOH at equivalence point. With the moles of NaOH and the volume in liters we can find the molar concentration of NaOH.
<em>Assuming the volume added of KHP was 25.50mL and the solution of NaOH contains 30.0mL (0.0300L), the concentration of the NaOH is:</em>
<em />
<em>Moles KHP = Moles NaOH:</em>
25.50mL = 0.02550L * (0.500mol / L) = 0.01275 moles KHP = Moles NaOH
<em>Molarity NaOH:</em>
0.01275 moles NaOH / 0.0300L =
<h3>0.425M NaOH assuming the volume of KHP was 25.50mL and the volume of the NaOH solution was 30.0mL</h3>
