Asolution is prepared by dissolving 10.8 g ammonium sulfate in enough water to make 100.0 ml of stock solution. a 10.00- ml sample of this stock solution is added to 50.00 ml of water. calculate the concentration of ammonium.

Construct the hypothetical phase diagram for metals a and b between room temperature (20c) and 700c, given the following information: * the melting temperature of metal a is 480c. • the maximum solubility of b in a is 4 wt% b, which occurs at 420c. • the solubility of b in a at room temperature is 0 wt% b. • one eutectic occurs at 420c and 18 wt% b–82 wt% a. • a second eutectic occurs at 475c and 42 wt% b–58 wt% a. • the intermetallic compound ab exists at a composition of 30 wt% b–70 wt% a, and melts congruently at 525c.• the melting temperature of metal b is 600c. • the maximum solubility of a in b is 13 wt% a, which occurs at 475c. • the solubility of a in b at room temperature is 3 wt% a.

In the following redox reaction which is the oxidizing agent and which is the reducing agent? alcl3 + na nacl + al

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?