B. Theory
The hypothesis that stand the test of time (often tested and never rejected) is called theory. A theory is supported by a great dealcof evidence.
Answer:
(3,2)
Explanation:
The x-co-ordinates above are 2 and 4
Their midpoint is 2+4/2
The y-co-ordinates above are 5 and -1
Their midpoint is 5+(-1)/2 = 2
The overall midpoint is (3,2)
Answer:
C. NaHCO3 → Na2CO3 + H2O + CO2
Explanation:
» For a balanced equation, the number of atoms of reactants and products must be equal.
» In equation C, the reactant side has one sodium atom while ptoduct side has 2 sodium atoms.
» The balanced equations mus be;
Answer:
0.16 moles of Carbon
Explanation:
The balanced reaction equation:
+ 
→ 
+ 
↑
The mole ratio of Carbon to Iron is 3 : 4 (since Fe2O3 is in excess)
i.e 3 moles of C produces 4 moles of Fe.
If 1 mole of Fe - 55.8g of Fe
? moles - 11.6g of Fe
= 
= 0.208 moles
But 3 moles of C - 4 moles of Fe
? moles of C - 0.208 moles of Fe
= 
= 0.16 moles of carbon.
I hope this explanation was clear and useful.
A calorimeter experiment is a set-up that provides insulation so that no heat escapes to the surroundings and all energy can be accounted for. It can be done at either constant volume or constant pressure. So, the answer to this is knowing the mass of water, the specific heat which is an empirical data, and the change in temperature which can be measured using a thermometer. This experiment could measure the mass of an unknown substance added or the specific heat of the substance or the calorimeter. <em>The answer is D.</em>
