Answer:
The liquid collected during distillation when the evaporated substance condenses. A separation technique that uses evaporation to separate substances. The mixture is heated so that one substance evaporates. The vapour is collected and condenses into a liquid.
<span>C2H5
First, you need to figure out the relative ratios of moles of carbon and hydrogen. You do this by first looking up the atomic weight of carbon, hydrogen, and oxygen. Then you use those atomic weights to calculate the molar masses of H2O and CO2.
Carbon = 12.0107
Hydrogen = 1.00794
Oxygen = 15.999
Molar mass of H2O = 2 * 1.00794 + 15.999 = 18.01488
Molar mass of CO2 = 12.0107 + 2 * 15.999 = 44.0087
Now using the calculated molar masses, determine how many moles of each product was generated. You do this by dividing the given mass by the molar mass.
moles H2O = 11.5 g / 18.01488 g/mole = 0.638361 moles
moles CO2 = 22.4 g / 44.0087 g/mole = 0.50899 moles
The number of moles of carbon is the same as the number of moles of CO2 since there's just 1 carbon atom per CO2 molecule.
Since there's 2 hydrogen atoms per molecule of H2O, you need to multiply the number of moles of H2O by 2 to get the number of moles of hydrogen.
moles C = 0.50899
moles H = 0.638361 * 2 = 1.276722
We can double check our math by multiplying the calculated number of moles of carbon and hydrogen by their respective atomic weights and see if we get the original mass of the hydrocarbon.
total mass = 0.50899 * 12.0107 + 1.276722 * 1.00794 = 7.400185
7.400185 is more than close enough to 7.40 given rounding errors, so the double check worked.
Now to find the empirical formula we need to find a ratio of small integers that comes close to the ratio of moles of carbon and hydrogen.
0.50899 / 1.276722 = 0.398669
0.398669 is extremely close to 4/10, so let's reduce that ratio by dividing both top and bottom by 2 giving 2/5.
Since the number of moles of carbon was on top, that ratio implies that the empirical formula for this unknown hydrocarbon is
C2H5</span>
Answer:
40 moles of O₂
30 moles of CO₂
Explanation:
Given parameters:
Number of moles of C₃H₄ = 10moles
Unknown:
Number of moles of CO₂ = ?
Solution:
The number of moles helps to understand and make quantitative measurements involving chemical reactions.
We start by solving this sort of problem by ensuring that the given equation is properly balanced;
C₃H₄ + 4O₂ → 3CO₂ + 2H₂O
We can clearly see that all the atoms are conserved.
Now, we work from the known to unknown. We know the number of moles of C₃H₄ to be 10moles;
1 mole of C₃H₄ reacted with 4 moles of O₂
10 moles of C₃H₄ will react with 10 x 4 = 40moles of O₂
1 mole of C₃H₄ will produce 3 moles of CO₂
10 moles of C₃H₄ will produce 10 x 3 = 30moles of CO₂
Answer:
0.302L
Explanation:
<em>...97.1mL of 1.21m M aqueous magnesium fluoride solution</em>
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In this problem the chemist is disolving a solution from 1.21mM = 1.21x10⁻³M, to 389μM = 389x10⁻⁶M. That means the solution must be diluted:
1.21x10⁻³M / 389x10⁻⁶M = 3.11 times
As the initial volume of the original concentration is 97.1mL, the final volume must be:
97.1mL * 3.11 = 302.0mL =
0.302L
Answer is: beryllium-10.
The diagram shows that atom has 4 protons, 5 neutrons and 2 valence electrons.
Atomic number is the number of protons, which is characteristic of a chemical element, beryllium (Be) is an element with atomic number 4.
Two valence electrons means that atom is from 2. group of periodic table, only beryllium is from that group; sodium (1. group), boron (13. group) and carbon (14. group).
Beryllium-10 has 6 neutrons, so it is isotope (different number of neutrons or mass number).