The question incomplete , the complete question is:
A student dissolves of 18.0 g urea in 200.0 mL of a solvent with a density of 0.95 g/mL . The student notices that the volume of the solvent does not change when the urea dissolves in it. Calculate the molarity and molality of the student's solution. Round both of your answers to significant digits.
Answer:
The molarity and molality of the student's solution is 1.50 Molar and 1.58 molal.
Explanation:
Moles of urea = 
Volume of the solution = 200.0 mL = 0.2 L (1 mL = 0.001 L)
Molarity of the urea solution ;
Mass of solvent = m
Volume of solvent = V = 200.0 mL
Density of the urea = d = 0.95 g/mL
(1 g = 0.001 kg)
Molality of the urea solution ;
The molarity and molality of the student's solution is 1.50 Molar and 1.58 molal.
Im working on science too!! I would help you but the attachment isn't pulling up..
Answer:
(a) Between methanol (CH₃OH) and glycerol (C₃H₅(OH)₃), the substance with the higher surface tension is glycerol (C₃H₅(OH)₃)
(b) Between tetrabromomethane (CBr₄) and chloroform (CHCl₃), the substance with the higher surface tension is chloroform (CHCl₃)
Explanation:
The surface tension of these substances at 20 °C given in mN/m, is as follows:
The surface tension of Methanol is 22.70
The surface tension of Tetrabromomethane is 26.95
The surface tension of Glycerol is 64.00
The surface tension of Chloroform is 27.50
(a) Between methanol (CH₃OH) and glycerol (C₃H₅(OH)₃), the substance with the higher surface tension is glycerol (C₃H₅(OH)₃)
(b) Between tetrabromomethane (CBr₄) and chloroform (CHCl₃), the substance with the higher surface tension is chloroform (CHCl₃)
In order to measure 0.733 moles of KBr from a 3.00 M solution, the chemist needs 244 mL of solution.
<h3>What is molarity?</h3>
Molarity (M) is a unit of concentration of solutions, and it is defined as the moles of a solute per liters of a solution.
- Step 1: Calculate the liters of solution required.
A chemist has a 3.00 M KBr solution and wants to measure 0.733 moles of KBr. The required volume is:
0.733 mol × (1 L/3.00 mol) = 0.244 L
- Step 2: Convert 0.244 L to mL.
We will use the conversion factor 1 L = 1000 mL.
0.244 L × (1000 mL/1 L) = 244 mL
In order to measure 0.733 moles of KBr from a 3.00 M solution, the chemist needs 244 mL of solution.
Learn more about molarity here: brainly.com/question/9118107
The value of the Gibbs free energy shows us that the reaction is spontaneous.
<h3>What is the Gibbs free energy?</h3>
The Gibbs free energy is a quantity that helps us to be able to determine the spontaneity of a reaction.
In order to obtain the Gibbs free energy, we must obtain the Ecell as follows; 0.799V - (-0.402V) = 1.201 V
Now;
△G = -nFEcell
△G = -(2 * 96500 * 1.201)
△G = -232kJ/mol
Learn more about free energy:brainly.com/question/15319033?
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