Answer:
Percent Yield Fe = 82.5%
Explanation:
The actual yield is the value produced after an experiment is conducted. The theoretical yield is the value calculated using the balanced chemical equation and atomic/molar masses.
To find the percent yield of iron (Fe), you need to (1) convert grams Al to moles Al (via atomic mass), then (2) convert moles Al to moles Fe (via mole-to-mole ratio from equation coefficients), then (3) convert moles Fe to grams Fe (via atomic mass), and then (4) calculate the percent yield. It is important to arrange the ratios in a way that allows for the cancellation of units. The final answer should have 3 sig figs to reflect the sig figs of the given values.
Atomic Mass (Mg): 24.305 g/mol
Atomic Mass (Fe): 55.845 g/mol
3 Mg + 2 FeCl₃ -----> 2 Fe + 3 MgCl₂
20.5 g Mg 1 mole 2 moles Fe 55.845 g
----------------- x ----------------- x ---------------------- x ----------------- =
24.305 g 3 moles Mg 1 mole
= 31.4 g Fe
Actual Yield
Percent Yield = ---------------------------------- x 100%
Theoretical Yield
25.9 g Fe
Percent Yield = -------------------- x 100%
31.4 g Fe
Percent Yield = 82.5%
By 'waves' do you mean sound waves? If so sound waves need to travel through things like solids, liquids and yup <u>gases. </u>When the waves travel they are vibrating the molecules in the matter. By doing this he molecules in solids are packed very tightly.
Answer:
Oxygen is the most contain in earth but you asked in a,b,c and d. So I'll choice A. aluminium.
Answer:
10 m
Explanation:
The mole fraction of FeCl₃ of 0.15, that is, per mole of solution, there are 0.15 moles of FeCl₃ and 1 - 0.15 = 0.85 moles of water.
The molar mass of water is 18.02 g/mol. The mass corresponding to 0.85 moles is:
0.85 mol × 18.02 g/mol = 15 g = 0.015 kg
The molality of FeCl₃ is:
m = moles of solute / kilogram of solvent
m = 0.15 mol / 0.015 kg
m = 10 m
Answer : Option C) 0.3 mol of Gold.
Explanation : Amongst the options given in the question, 0.3 mol of Au is the greatest in mass in grams.
As 0.3 mol X atomic weight of Au (196.966) = 59.088 grams;
Silver has 0.5 mol X atomic weight of Ag (107.86) = 53.93 grams;
The other options are not relevant as they deal in the atomic range which has mass value very less as compared to the moles of elements.
Therefore, it is clear that Au has the greatest mass amongst the given choices.
