more chemsistry help...?

Question

When Hydrochoric acid is applied to a seashell, a colorless gas rapidly evolves. This indicates that the shell probably contains:
Phosphate
Carbonate
Chloride
Sulfate

Which of the following is most important in current industry production?
Be
W
Na
Al

Which of the following elements is most unlike the others?
Mg
Ca
Br
Pb

Answer 1

Carbonate - the shell would be emitting CO2

Many different answers to second question but Beryllium is used for bomb making as a neutron source: alpha or gamma in and neutron out. It is a controlled material. Your teacher may be looking for tungsten (W) since it adds strength to steel and is also used in welding rods. Aluminum is used almost everywhere and our consumption of it is immense.

Again, many answers. Bromine is a non-metal and turns into a gas (is volatile) at room temperature. All the others are metals. I would go with that. However, lead (Pb) is the heaviest and is the end of all three natural decay chains. It is denser than all the others, too. Magnesium is the only one that oxidizes (burns) easily.

Answer 2

Question 1

This test is for a carbonate as the gas released is carbon dioxide.

Question 2.

This is probably Al, Aluminium, as it has the most uses.

Question 3

Br as this is bromine, as there rest are metals.

Answer 3

Carbonate

Probably tungsten (used in lightbulbs) or Aluminum (used in everything)

Bromine (it is a liquid while the others are solids. Also, the others are metals and Bromine isn't)

Answer 4

1) Carbonate CO2 is emitted

2) Aluminium

3) Br is not a metal

Answer 5

(a) ____ (s) + C2 (s) => Fe (l) + CO (g) You are provided with Carbon, Iron and Carbon Monoxide. Because this Fe has a +3 charge and Oxygen has a -2 charge, your Iron ore will 2Fe and 3O to cancel out the charges ... or Fe2O3 Fe2O3 (s) + C2 (s) => Fe (l) + CO (g) Now to balance: 2 Fe, 3 O, 2 C => 1 Fe, 1 C, 1 O Double the Fe2O3, triple the C2, multiply Fe by 4 and multiply CO by 6 2Fe2O3 (s) + 3C2 (s) => 4Fe (l) + 6CO (g) 4 Fe, 6O, 6C => 4 Fe, 6 C, 6 O Balanced. (b) Mole ratio of Fe2O3 to Fe is 2 to 4 or 1:2 415 kg of Iron MW of iron is 55.845 kg/kg mol Mol of Iron = 415 kg / (55.845 kg / kg mol) = 7.43 kg mol of Fe Which means you need 7.43 kg mol * (1 kg mol Fe2O3 / 2 kg mol Fe) Or 3.72 kg mol Fe2O3 MW of Fe2O3 is (2*55.845 kg + 3*15.999 kg) / kg mol ... 159.7 kg / kg mol Mass = 3.72 kg mol * (159.7 kg/kg mol) Kilograms of Iron(III) Oxide required: 594 kg

Answer 6

carbonet,Al,Br