Answer:
B) C3H3O and C6H6O2
Explanation:
Given data:
Molar mass of compound = 100 g/mol
Percentage of hydrogen = 5.45%
Percentage of carbon = 65.45%
Percentage of oxygen = 29.09%
Empirical formula = ?
Molecular formula = ?
Solution:
Number of gram atoms of H = 5.45 / 1.01 = 5.4
Number of gram atoms of O = 29.09/ 16 = 1.8
Number of gram atoms of C = 65.45 / 12 = 5.5
Atomic ratio:
C : H : O
5.5/1.8 : 5.4/1.8 : 1.8/1.8
3 : 3 : 1
C : H : O = 3 : 3 : 1
Empirical formula is C₃H₃O.
Molecular formula:
Molecular formula = n (empirical formula)
n = molar mass of compound / empirical formula mass
Empirical formula mass = 12×3 + 1.01 ×3 + 16×1 = 55.03
n = 100 / 5503
n = 2
Molecular formula = n (empirical formula)
Molecular formula = 2 (C₃H₃O)
Molecular formula = C₆H₆O₂
Potassium and Chloride forms an ionic bond.
(K+) + (Cl-) = KCl
Potassium is under Group IA (Alkali Metal), wherein elements under this group can easily lose electrons.
Chlorine is under Group VII (Halogens), in which these elements can gain electrons easily.
The inner shell electrons on potassium will merge with the outer shell of electrons of chlorine to make potassium chloride.
Answer:
Reaction 1 = -462.5 kJ/mol
Reaction 2 = -572 kJ/mol
Magnesium combustion = -601.83 kJ/mol
Answer: The correct option is A,
--> a.) Transition metals have partially filled d subshells.
Explanation:
Transition elements are all metals of economic importance. They are found in the d- lock of the periodic table between group 2 and 3. They occupy three rows, with ten elements in each row. The term 'transition metals' refers only to an element which has PARTIALLY filled d orbitals. Typical example of transition metals include iron (Fe).
They have partially filled 3d orbitals which are responsible for the special properties of the metals. These include:
--> Physical properties: the transition metals have high boiling and melting points. They are hard, dense and lustrous. They are also good conductors of heat and electricity.
--> Chemical reactivity: In the s- block and p-block, the chemical properties of the elements in the same period vary, often quite markedly, from left to right. This does not happen with the transition metals because electrons are added progressively to the inner d-orbitals.
--> Variable oxidation states: they have variable oxidation states because 3d electrons are available for bond formation.
Answer:
Melting and evaporation both represent changes in matter that involve behavior at the molecular level.