1 Hydrogen 1s1
2 Helium 1s2
3 Lithium 2s1
Answer:
The physical and chemical properties of the product do not match the properties of the reactant.
Explanation:
Chemical change:
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:
Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood
Boiling of egg: that change the chemical composition of protein in the egg .
The reaction of Hydrogen and oxygen:
H 2 (g) + O 2 (g) -------------------------------------> 2H 2O (l)
The reaction between sugar and oxygen form a product which is different from the reactant that's why it indicate the occurrence of chemical reaction.
While in case of physical changes just state of matter are changed. Properties remain same.
Answer:
The empirical formula = molecular formula = C13H18O2
Explanation:
in 100% compound we have 75.6 % Carbon ( Molar mass = 12g/mole), 8.80% hydrogen ( Molar mass = 1.01 g/mole) and 15.5% Oxygen (Molar mass = 16.01 g/mole).
Carbon: 75.6g / 12 = 6.29
Hydrogen: 8.80/ 1 = 8.80
Oxygen: 15.5/ 16 = 0.97
⇒0.97 is the smallest so we divide everything through by 0.97
C: 6.29 / 0.97 = 6.48 ≈ 6.5
H: 8.80 /0.97 = 9
O: 0.97 / 0.97 = 1
To get rid of decimals, we multiply by 2
C: 6.5 x 2 = 13
H: 9 x 2 = 18
O: 1 x 2 = 2
The empirical formula = C13H18O2
13x 12g/mol + 18x1g/mol + 2x 16g/mol = 156 + 18 + 32 = 206g/mol which is the molar mass of ibuprofen
The empirical formula = molecular formula = C13H18O2
5 Valence electrons .......... Hope it helps, Have a nice day:)
