Consider this picture depicting the hydration of an atom or ion by water molecules.  Of the choices below, what is the only atom or ion that the yellow particle in the center can be?   Group of answer choices A:K+ ion B:oxygen atom in ethanol (CH3CH2OH) C:Cl- ion D:nitrogen atom in ammonia (NH3)   The solubility of sulfur hexafluoride (SF6) gas in water is 2.1 x 10-4 M at 20 oC.  Based on the choices below and without doing any calculations, what is the most likely solubility of SF6 if the solution temperature is lowered to 5 oC? Group of answer choices A:2.1 x 10-4 M B:5.6 x 10-4 M C:2.1 x 10-6 M D:1.0 x 10-4 M

A student task is to prepare 3 glucose (C6H12O6) solutions with different concentration. If the student must first prepare 100.0 mL of each solution. The student was given only 4.00 grams of glucose and 320.0 mL of water. At the end of the experiment, the student must end up with at least 80.0 mL of 0.200 M, 90.0 mL of 0.025 M, 100.0 mL of 0.0010 M glucose solution. The total volume of all of the solutions must not 320.0 mL solution. Be very specific.

An solution of antifreeze is prepared by mixing 22.0 mL of ethylene glycol (density= 1.11 g/mol; molar mass= 62.07 g/mol) with 50.0 mL H2O (density= 1.00 g/mol) at 25° C. If the density of the antifreeze solution is 1.07 g/mL, what is the molarity?

A 0.15 M solution of HCl is used to titrate 30.0 mL of a Ca(OH)2 solution of unknown concentration. If 140.0 mL of HCl is required, what is the normality of the Ca(OH)2 solution? What is the molarity?

Chloride ion concentration in the fluid surrounding human cells is approximately 25mM (millimolar). How many grams of NaCl must be dissolved in 6 L of solution to make a 25 mM NaCl(aq) solution?

What mass of cobalt III hydroxide, Co(OH)3 is needed to make 1.2 liters of a 0.21 M cobalt III hydroxide solution? What volume of barium chloride, BaCl2 is needed to make a 2.5 M barium chloride solution with 0.25 mol BaCl2? Calculate the molarity of 14.2 grams of sugar, C12H22O11 in 1,500. mL of solution. How many grams of potassium nitrate, KNO3 are required to prepare 1.50 L of a 2.80M solution? A solution is prepared by mixing 200.0 g of water, H2O, and 200.0 g of ethanol, C2H5OH. Determine the mole fractions of each substance. Calculate the molality of 15.0 grams of KBr dissolved in 750.0 mL pure water. What mass of ammonium sulfate, (NH4)2SO4 must be added to prepare 400.0 g of a 7.0% solution of ammonium sulfate in water?

A bottle of anhydrous copper(II) sulfate was accidentally left uncapped for an afternoon, allowing it to pick up water from the environment. To determine the degree to which the compound was hydrated, a sample was analyzed. The initial weight of the partially hydrated copper(II) sulfate was 9.782. After drying to constant weight, the weight was 7.232. How may waters of hydration are present?

You are standardizing a NaOH solution and find that it requires 21.71mL of NaOH to neutralize 1.589g of KHP (molar mass 204.22 g/mol). What is the NaOH concentration in M (mol/L)?

What is the percent-by-mass concentration of acetic acid (CH3COOH) in a vinegar solution that contains 65.20 g acetic acid in a 1.000−L solution? The density of this solution is 1.005 g/mL.

An aqueous solution of fructose (MM = 180.2 g/mol) has a molality of 4.87 m and a density of 1.30 g/mL. What is the molarity of fructose in the solution?