Answer:
=37.83783784
Explanation:
Find the total sum of all coins,
which is 37, take the number of pennies and the total of all coins put in parenthesis( 14/37) like so and than * times them by 100
you equation should look like this
(14/37)* 100= and than the answer shown above should be the one you received. I have checked this with multiple calculators, it should be accurate.
<span>0.925 grams if using hydrochloric acid in the reaction.
0.462 grams if using sulfuric acid in the reaction.
0.000 grams if using nitric acid in the reaction.
Assuming you're using HCl or a similar acid for this reaction, the equation for the reaction is:
Zn + 2 HCl ==> ZnCl2 + H2
So each mole of zinc used, produces 1 mole of hydrogen gas, or 2 moles of hydrogen atoms. So we need to look up the atomic weights of both zinc and hydrogen.
Atomic weight zinc = 65.38
Atomic weight hydrogen = 1.00794
Moles zinc = 30.0 g / 65.38 g/mol = 0.458855919 mol
Since we produce 2 moles of hydrogen atoms per mole of zinc, multiply by 2 and the atomic weight of hydrogen to get the mass of hydrogen produced. So
0.458855919 * 2 * 1.00794 = 0.92499847 grams.
Rounding to 3 significant figures gives 0.925 grams.
To show the assumption of the acid used, the balanced equation for sulfuric acid would be
Zn2 + H2SO4 ==> Zn(SO4)2 + H2
Which means that for every mole of zinc used, 1 mole of hydrogen gas is generated (half that produced via hydrochloric acid).
If nitric acid were used, the reaction is
4Zn + 10HNO3 ==> 4Zn(NO3)2 + N2O + 5H2O
Which means that NO hydrogen gas is generated.
The only justification for assuming hydrochloric acid is used is that it's a fairly common acid that's easy to obtain. But as shown above with 2 alternative acids, the amount of hydrogen gas generated is very dependent upon the exact chemical reaction occurring and asking "How many grams of hydrogen are produced if 30.0 g of zinc reacts?" is a rather silly question unless you specify EXACTLY what the reaction is.</span>
Answer:
The answer is below
Explanation:
Because various factors can affect the actual value of the titration outcome. Some of these factors can range from errors from a researcher also known as human error, misreading the quantities, researcher's perception of the color, or wrong procedure in carrying out the experimentation.
Hence, in order to avoid such error, a researcher needs to be thorough during the process of experimentation, and using gross reading can help to avoid these errors when the titre value is eventually determined.
Answer:
premium: 91 octane rating
Explanation:
Octane number refers to the percentage or volume fraction of isooctane in a fuel.
The octane number gives a picture of how safe a fuel is for an engine. The higher the octane rating the lesser the tendency of the fuel to cause knocking of the engine.
The type of gasoline with the highest percentage of octane among the options is premium.
Answer:233 Joules/K
Explanation:
∆H= 26.5KJmol-1
Kelvin temperature = 34.6 + 273 = 307.6 K
No of moles= 2.7 moles
2.70 mole x 26.5 kJ/mole = 71.55kilojoules
∆S=71.55 kilojoules / 307.6 K = 0.233 kilojoules/ K
Convert to JK-1
0.233 kilojoules/ K x 1000 Joules/kilojoule = 233 Joules/K
