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:
1. (S,O) < (Se,S) < (C,H) = (H,I) = (H,F) < (Si,Cl) < (K,Br)
Explanation:
The covalent character always increases down the group, this is because ionic character decreases down the group and also electronegativity.
In the same way, Covalent character always decreases across a period because electronegativity increases across a period.
The higher the electronegativity values between the two atoms, the more ionic it will be.
Answer:
12.32 L.
Explanation:
The following data were obtained from the question:
Mass of CH4 = 8.80 g
Volume of CH4 =?
Next, we shall determine the number of mole in 8.80 g of CH4. This can be obtained as follow:
Mass of CH4 = 8.80 g
Molar mass of CH4 = 12 + (1×4) = 12 + 4 = 16 g/mol
Mole of CH4 =?
Mole = mass/Molar mass
Mole of CH4 = 8.80 / 16
Mole of CH4 = 0.55 mole.
Finally, we shall determine the volume of the gas at stp as illustrated below:
1 mole of a gas occupies 22.4 L at stp.
Therefore, 0.55 mole of CH4 will occupy = 0.55 × 22.4 = 12.32 L.
Thus, 8.80 g of CH4 occupies 12.32 L at STP.
Answer:
3.064 $
Solution:
First of all we will find the number of pounds contained by one Kg. Therefore, it is found that,
1 Kilogram = 2.20462 Pounds
Hence, as given,
1 Pound of Margarine costs = 1.39 Dollars
So,
2.20462 Pounds Margarine will cost = X Dollars
Solving for X,
X = (2.20462 Pounds × 1.39 Dollars) ÷ 1 Pound
X = 3.064 Dollars
Answer:
The answer is the third one which is 24 (glucose)
