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• what is the mass in grams of 1.204 x 10²³ molecules of H2O?
• how many formula units are there in 0.175 g of LiF
Calculate the total hardness of a sample of water containing following impurities 16.2
mg/L of Ca(HCO3)2, 11.1 mg/L of CaCl2, 60 mg/L of CaSO4 and Mg(HCO3)2, 11.2 mg/L
of MgCl2, 60 mg/L of MgSO4 and 19 mg/L of Mg(NO3)2.
How many moles of water are equal to 1.204 x 10²³ molecules of H2O?
provide a solution.
- In acidic solution, dichromate ion oxidizes 0xalic acid, H2C2O4 (aq), to CO2 (g) in a reaction with Eocell =1.81V.
Cr2O72-(aq) + 3 H2C2O4(aq) + 8H+(aq) → 2Cr3+(aq) + 7H2O + 6CO2(g) ,
Which formula listed below is a polyatomic ion?
Select one:
a. Na+Cl–
b. None of the above
c. HCl
d. H2SO4
Write a balanced chemical equation, including phases, for the single displacement reaction you observed in Experiment 3. Be sure that the reaction products make sense based on your observations.
Compare 1.0 mol/L sodium hydroxide with 1.0 mol/L ammonia (written as ammonium hydroxide) by recreating similar diagrams of dissociation and concentration as those provided to you for the acid comparison. Assume ammonia dissociates only 1%. What would you expect to see if you tested the conductivity and pH of each? Why is there a difference in reactivity if there is 1 mole of acid in a given litre?
The mass of a beaker is 5.833 g. After 3.00 mL of a certain pure liquid, is added into the beaker, the combined mass of the beaker and the liquid sample is 8.613 g. From the data, what is the measured density of the liquid?
John used an empty beaker that has a mass of 43.126 g. In a separate jar, he had a mixture of salt and sand. He transferred two scoops of salt and sand mixture to the beaker. The overall mass was 55.449 g. As you know salt is soluble in water, he added enough water to the beaker with salt and sand mixture to completely dissolve the salt. He filtered the mixture and dried what was left in the filter. The mass of that residue was 8.200 g. Based on the experiment calculate:
1. The mass of salt: _____
2. The mass of sand: _____
3. The mass of the mixture (salt + sand): _____
You have 1 m3 of wood and 1 m3 of aluminum. Which is heavier? Prove your answer with calculation.
