Other Chemistry Answers

A 24-hr urine specimen was diluted to 2.000 L. After the solution was buffered to pH 10, a 10.00-mL aliquot was titrated with 23.57 mL of 0.004590 M EDTA. The calcium in a second 10.00-mL aliquot was isolated as CaC₂O_4(s), redissolved in acid, and titrated with 10.53 mL of the EDTA solution. Assuming that 15 to 300 mg of magnesium and 50 to 400 mg of calcium per day are normal, did this specimen fall within these ranges? 

With the aid of diagram show how ammonia molecule is formed

It was found that in the analysis for the mercury content in soil required 1.5 grams sample to obtain a relative standard deviation for sampling of ±2.0%. To obtain a relative sampling error of no more than 0.80% at the 95% confidence level, what is the number of samples required?

It was found that in the analysis for the mercury content in required 1.5 g sample to obtain a relative standard deviation for sampling of %To obtain a relative sampling error of no more than % at the 95% confidence level, what is the number of samples required?

The decomposition reaction of hydrogen iodide at 508oC.

2HI (g) → H2

(g) + I2(g)

Time (s) 0 50 100 150 200 250 300 350

Concentration

of HI (M)

0.1000 0.0716 0.0558 0.0457 0.0387 0.0336 0.0296 0.0265

(a) Plot the concentration time graph.

(b) Calculate from the graph;

i. Average rate between 50 and 250 seconds

ii. Instantaneous rate at 200 s

iii. Initial instantaneous rate