General Chemistry Answers

Ammonium phosphate NH43PO4 is an important ingredient in many fertilizers. It can be made by reacting phosphoric acid H3PO4 with ammonia NH3.

What mass of ammonium phosphate is produced by the reaction of 8.4g of ammonia?

Round your answer to 3 significant digits.

For the reaction 2 Cu₂O (s) + O₂ (g)  →

→ 4 CuO (s), calculate ΔG^o (in kJ) at 500 K.

if an equation is balanced properly, both side of the equation must have the same number of

Two bulbs A and B of equal volumes connected through stopcock (kept open) contained 0.7 mol of H_{2} gas at pressure of 0.5 atm and 27°C. The bulb A is heated to 127°C keeping bulb B at 27°C. Calculate final pressure and molar distribution of H_{2} in two bulbs.

A student measures the range of sound frequencies that the human ear can hear by playing sounds for volunteers between 10 and 30,000 Hertz and asking them to raise their hand if they were able to hear it. What type of variable is the independent variable in this experiment?

• A. Categoric
• B. Continuous
• C. Ordered
• D. Discrete

A 0.3304-g sample of brass (containing lead, zinc, copper, and tin) was dissolved in nitric acid. The sparingly soluble SnO2.4H2O was removed by filtration, and the combined filtrate and washings were then diluted to 500.0 mL. A 10.00-mL aliquot was suitably buffered; titration of the lead, zinc, and copper in this aliquot required 34.78 mL of 0.002700 M EDTA. The copper in a 25.00-mL aliquot was masked with thiosulfate; the lead and zinc were then titrated with 25.62 mL of the EDTA solution. Cyanide ion was used to mask copper and zinc in a 100-mL aliquot; 10.00 mL of the EDTA solution was needed to titrated the lead ion. Determine the composition of the brass sample; evaluate the percentage of zinc by difference

Titration of Ca2+ and Mg2+ in a 50.00-mL sample of hard water required 23.65 mL of 

0.01205 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate 

Mg2+ as Mg(OH)2. The supernatant liquid was titrated with 14.53 mL of the EDTA solution. 

Calculate

a) The total hardness of the water sample, expressed as ppm CaCO3

b) The concentration of CaCO3 and MgCO3 in the sample in ppm

A mixture of 206.0 g

206.0 g of 

Cl2 and 45.0 g

45.0 g of P

P reacts completely to form 

PCl3 and PCl

5

.

PCl5. Find the mass of 

PCl5 produced.

32.00mL of hydrogen gas (at SLC) was generated in the process of HCl reacting with magnesium metal. How many molecules of HCl were required for this reaction?