# Science

## At 20°C, a saturated solution holds 65.2 g of KBr in 100 g of water. What is the mass percent of KBr in water? If the temperature for the solution is raised to 60°C, but no more solute is added, would you expect the solution to be saturated, unsaturated or supersaturated? Why?

EXPERT ANSWER Explanation: The meaning of mass percentage is that the amount of solute in gram present in per 100g of the solution. Given data; mass of solute(KBr) = 65.2 g mass of solvent(water) = 100 g total mass of solution = 165.2 g Formula: (% m/m) mass percent = ( mass of the solute …

## 1. The actual solubility of KCl in water at 20°C is given in a solubility table as 34.0 g KCl/100 g water, which is equal to a molality of 4.56 m. How does your result compare to your experimental molality?Experimental molality is 50%, Experimental value is 48.7

The Actual Solubility Of KCl In Water At 20°C Is Given In A Solubility Table As 34.0 G KCl/100 G Water, Which Is Equal To A Molality Of 4.56 M. How Does Your Result Compare To Your Experimental Molality Experimental molality is 50%, Experimental value is 48.7 EXPERT ANSWER

## The quenching of tryptophan fluorescence by dissolved O2 gas was monitored by measuring emission lifetimes at 348 nm in aqueous solution. Determine the quenching rate constant for this process from the following data.

The Quenching Of Tryptophan Fluorescence By Dissolved O2&Nbsp;Gas Was Monitored By Measuring Emission Lifetimes At 348 Nm In Aqueous Solution. Determine The Quenching Rate Constant For This Process From The Following Data. [O2] (10-2mol dm-3) 0 2.3 5.5 8 10.8 T/ns    2.6 1.5 0.92 0.71 0.57 EXPERT ANSWER Consider the Stern Volmer equation t0/t …

## Spell out the full name of the compound.Part A,What sugar is the C?3 epimer of D-ribose?Part B,What sugar is the C?5 epimer of L-gulose?Part C,What sugar is the C?4 epimer of L-ribose?Part D,What sugar is the C?4 epimer of D-lyxose?

Problem 16.4 Spell out the full name of the compound. Part A What sugar is the C?3 epimer of D-ribose? Part B What sugar is the C?5 epimer of L-gulose? Part C What sugar is the C?4 epimer of L-ribose? Part D What sugar is the C?4 epimer of D-lyxose? EXPERT ANSWER