Chemistry ch 6 and lab

Chemistry ch 6 and lab - Ignition of MgNH 4 PO 4 ∙ 6H 2 O...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
The hydrogen atom can absorb light of wavelength 2626 nm. In what region of the electromagnetic spectrum is this absorption found? Determine the initial and final values of n associated with this absorption. Give the values for n, l, and m l for (a) each orbital in the 2p subshell, (b) each orbital in the 5d subshell. The following percentages of chloride were found in a sample: 22.52%, 22.14%, 22.61%, and 22.75%. (a) Find the mean, the standard deviation, and the relative standard deviation. (b) Can any result be discarded? What is the percent phosphorus in MgKPO 4 ∙ 6H 2 O? MgKPO 4 ∙ 6H 2 O has a solubility of 0.023 g/100 mL in water. Suppose a 5.02 g sample were washed with 20 mL of water. What fraction of the MgNH 4 PO 4 ∙ 6H 2 O would be lost? MgNH 4 PO 4 ∙ 6H 2 O loses H 2 O stepwise as heated. Between 40 and 60 C the monohydrate is formed, and above 100 C the anhydrous material is formed. What are the phosphorous percentages of the monohydrate and of the anhydrous material?
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Ignition of MgNH 4 PO 4 ∙ 6H 2 O produces NH3, H 2 O, and magnesium pyrophosphate, Mg 2 P 2 O 7 . Complete and balance the equation for this reaction. If 2.50 g of MgNH 4 PO 4 ∙ 6H 2 O are ignited, how many grams of Mg 2 P 2 O 7 would be formed? What is the percentage of P 2 O 5 in Mg 2 P 2 O 7 ? Today, sodium content in food is an important health concern. How many milligrams of sodium are present in one ounce of table salt (NaCl)? A 50.0 mL sample of a 1.00 M solution of CuSO 4 is mixed with 50.0 mL of 2.00 M KOH in a calorimeter. The temperature of both solutions was 20.2° C before mixing and 26.3° C after mixing. The heat capacity of the calorimeter is 12.1 J/K. From these data, calculate ∆H for the process CuSO 4 (1 M ) + 2KOH (2 M ) → Cu(OH) 2 (s) + K2SO 4 (0.5 M ) Assume the specific heat and density of the solution after mixing are the same as those of pure water....
View Full Document

This document was uploaded on 10/23/2010.

Ask a homework question - tutors are online