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Solution calculations: Give answers to 1 decimal place.   A 150 mL sample of saltwater is evaporated to dryness. A residue of salt weighing 37.9 g is left behind. Calculate the %(w/v) of the original saltwater. [red21] %   A solution is made by mixing 100.0 ml of alcohol with enough water to give 250. mL of solution. What is the %(v/v) concentration of alcohol in the solution? [red22] %

Convert the following numbers into scientific notation. Format: number(space)x(space)10^number   13546     [red3]   0.001354 [red4]

Solutions of NaOH and HCl react according to the following equation:   NaOH  +  HCl –> NaCl +  H2O   What volume of 0.250 M NaOH solution contains 0.220 mol of NaOH? Give answer to 2 decimal places. [red23] liters   What volume of a 0.200M NaOH solutions is needed to exactly react with 0.150 mol of HCl?Give answer to 2 decimal places. [red24] liters

The area of a rectangle is the length times the width. What is the area of a rectangle that is 2.5 m by 2.0 m. Calculate the area in square meters and in square centimeters. Answer in whole numbers.   Area = [red1] square meters   Area = [red2] square millimeters

An irregularly shaped object weighs 60 grams. A researcher wants to know its density so she takes a graduated cylinder and fills it to 50 ml. When the object is placed in the cylinder the water volume increases to 88 ml. What is the density of the object. Give the answer to 1 decimal place. [red38] g/ml

Given the following reaction:               CaCO3 –>  CaO + CO2   Calculate the number of moles of CO2 that will be generated when 650 grams of CaO is produced. Give the answer to 2 decimal places. [red27]moles CO2

Complete and balance the following molecular equations. Include appropriate phase notation.  NaOH (aq) +  FeCl3 (aq) 

Which situation is most consistent with the facial feedback hypothesis?​

Lie detector tests use what assumption in detecting liars?​

Shortly after finishing his fifteen-mile run, Georgio sees a handsome man waiting at the bus stop. Georgio feels attracted to this man and introduces himself. They agree to meet later for lunch. During lunch, however, Georgio decides that the man is not nearly as attractive or interesting as he originally thought. What was most likely occurring when Georgio first met the “handsome” stranger?​