Answer:
a) 
2 moles of Zinc sulphide in solid form reacts with 3 moles of Oxygen in gaseous form to give 2 moles of Zinc oxide in solid form and 2 moles of sulphur dioxide in gaseous form.
b) 
1 mole of calcium hydride in solid form reacts with 2 moles of liquid water to give 1 mole of calcium hydroxide dissolved in water and 2 moles of hydrogen in gaseous form.
The chemical reactions are written by writing the chemical formula of the reactants on left side of the arrow followed by chemical formula of the products. The number of atoms of each element must be balanced to follow the law of conservation of mass.
Answer:
A. The model could not explain how alpha particles could be deflected at large angles.
Explanation:
The plum pudding model of the atom was proposed by J. J Thomson. He suggested that that an atom is made up of dense particles of electrons surrounded by positive charges.
From the Gold foil experiment carried out by Ernest Rutherford, he noticed that the bulk of the alpha particles targeted at the foil passed through and a little fraction was heavily deflected back.
Rutherford then presented his nuclear model from here. He suggested a massive, dense and tiny nucleus where the protons and neutrons are located. The space outside the mass is dominated by orbiting electrons.
Answer:
By a factor of 12
Explanation:
For the reaction;
A + 2B → products
The rate law is;
rate = k[A]²[B]
As you can see, the rate is proportional to the square of the concentration of A and the of the concentration of B
.
Let's say initially, [A] = x, [B] = y
The rate law in this case is equal to;
rate1 = k. x².y
Now you double the concentration of A and triple the concentration of B.
[A] = 2x, [B] = 3y
The new rate law is given as;
rate2 = k . (2x)². (3y)
rate2 = k . 4x² . 3y
rate2 = 12 k . x² . y
Comparing rate 2 and rate 1, the ratio is given as; rate 2/ rate 1 = 12
Therefore the rate has increased by a factor of 12.
Answer:
The attractive force between them decreases
Explanation:
This is because they become localised.
Answer:
C
Explanation:
It afffects changes in pressure and temperature not melting and boiling points
