A solution has pH = 0 its H+ ion concentration is__________________?
A. 1 x 10-1
B. 1 x 10-14
C. 1 x 10-7
D. 1
Which of the following is not characteristics of reversible reaction__________________?
A. whole amount of reactant does not change into product
B. chemical equilibrium is established
C. a catalyst changes the direction of reaction
D. rate of forward reaction decreases as reaction proceeds
Which of the following theories is superior to others__________________?
A. VSEPR
B. VBT
C. MOT
D. none of the above
The balanced chemical equation for the reaction which occurs when Be is added to water is____________?
A. Be+2H2O?Be (OH)2+H2
B. Be+H2O?Be (OH)2+H2
C. Be+H2O?[Be (OH)4]+2+H2
D. no reaction
Which of the solid does not contain covalent bond__________________?
A. copper
B. ice
C. diamond
D. graphite
The hardest of the following solids is__________________?
A. sodium
B. diamond
C. graphite
D. magnesium
Which statement is consistent with Hunds rule ?
A. Electrons fill orbitals with parallel spins until all the orbitals of the same energy are half filled then they go into sub-shells with anti-parallel (opposite) spin.
B. The electrons in the same atom cannot have the same four quantum numbers
C. There is maximum of two electrons is an orbital.
D. None
When an electron is moving with velocity of 2.188 x 106 ms-1 in the first orbit of Bohrs model of hydrogen. The de Broglie wavelength of electron is______________?
A. 0.33 nm
B. 0.34 nm
C. 0.35 nm
D. 0.36 nm