Answer: they are the same.
Explanation:
1) Sucrose is a compound with chemical formula C₁₂H₂₂O₁₁
2) That means that all molcules of sucrose will have the same kind of atoms in the same proportion, whic is to say same composition:
12 atoms of C: 22 atoms of H: 11 atoms of O, per each molecule of sucrose.
3) For this question you can rely in the definition of compound: a pure substance formed by the combination of two or more elements always in the same ratio (same composition).
4) That also implies, that all the molecules of sucrose have the same properties.
A compound consists of 2 or more elements that are combined chemically in such a way that the elements themselves can no longer be identified by their individual properties. So the Answer is A.
First calculate the moles of N2 and H2 reacted.
moles N2 = 27.7 g / (28 g/mol) = 0.9893 mol
moles H2 = 4.45 g / (2 g/mol) = 2.225 mol
We can see that N2 is the limiting reactant, therefore we
base our calculation from that.
Calculating for mass of N2H4 formed:
mass N2H4 = 0.9893 mol N2 * (1 mole N2H4 / 1 mole N2) * 32
g / mol * 0.775
<span>mass N2H4 = 24.53 grams</span>
The whole Activity , poem and paragraph is missing in the question.
Answer:
(1) Liquid A
(2) Solid A
Explanation:
Using this part of the given poem
Substances and mixtures behave differently,
During boiling and melting most especially
Boiling point of substance is fixed while mixture is not
Substance melts completely but mixture does not
The boiling point of the Pure substance remain fixed after reaching its boiling point this is shown by Liquid A
Solid A is melting completely so Solid A is a pure substance.
Explanation:
Half life is simply the amount of time it takes for half of a substance to decompose.
Options;
- Carbon-14 has a half-life of 5,730 years. A 30 gram sample will be 10 grams after 5,730 years. This is incorrect. After 5730 years, 15g of the sample ought to remain.
- Nickel-59 has a half-life of 76,000 years. A sample would go through 3 half-lives in 228,000 years. This is correct. 3 * 76000 = 228,000
- Hafnium-182 has a half-life of 9 million years. A 38 gram sample would be 4.75 grams in 27 million years. This is incorrect. Mass after 3 half lives (27/9) = 9.5 (38 / 2 / 2)
- Iron-60 has a half-life of 1.5 million years. In 6 million years a 40 gram sample would be reduced to 10 grams. This is incorrect. Mass after 4 half lives (6 / 1.5) = 2.5 gram (40 / 2 / 2 /2 / 2)
- Lead-202 has a half-life of 52,500 years. The original sample must have been 120 grams if you have a 60 gram sample after 105,000 years. This is incorrect. Original sampe = 240 gram. So after 2 half lives (105,000/52500), mass left = 60 (240 / 2 /2)
