Answer:
459.126 grams of calcium chloride is needed to prepare 2.657 L of a 1.56 M solution
Explanation:
Molarity is a measure of the concentration of a solute in a solution that indicates the amount of moles of solute that appear dissolved in one liter of the mixture. In other words, molarity is the number of moles of solute that are dissolved in a given volume.
The Molarity of a solution is determined by the following expression:

Molarity is expressed in units 
In this case:
- Molarity: 1.56 M= 1.56

- Number of moles of calcium chlorine= ?
- Volume= 2.657 liters
Replacing:

Solving:
Number of moles of calcium chlorine= 1.56 M* 2.657 liters
Number of moles of calcium chlorine= 4.14 moles
In other side, you know:
- Ca: 40 g/mole
- Cl: 35.45 g/mole
Then the molar mass of the calcium chloride CaCl₂ is:
CaCl₂= 40 g/mole + 2* 35.45 g/mole= 110.9 g/mole
Now it is possible to apply the following rule of three: if in 1 mole there is 110.9 g of CaCl₂, in 4.14 moles of the compound how much mass is there?

mass= 459.126 g
<u><em>459.126 grams of calcium chloride is needed to prepare 2.657 L of a 1.56 M solution</em></u>
Answer: The electronic configuration of potassium atom in excited state is 
Explanation:
There are 2 states classified under energy levels:
1. Ground state: This is the lower energy state which is termed as stable state.
2. Excited state: This is the upper energy state and is termed as the unstable state. All the electrons which are present in this state always come back to the ground state.
Ground state electronic configuration of potassium (Z = 19) : 
As, only 1 electron can freely move to upper state. Hence, the excited state electronic configuration of potassium will be: 
Answer:
False.
Explanation:
The given statement is false because for hot vacuum filtration, the filter paper should be wet rather than dry when pouring the hot solution into the Buchner funnel. This is because The possible explanation the filter paper needs to be wetted is not only to allow it to adhere to the funnel, but also to promote the solute to filter down readily across its pores of the paper without wetting it (this is true for organic and aqueous solvents).
Ira is working in a lab with a unknown solution. when he inserts the electrical conductivity tester in the in known, the bulb begins to glow brightly. which of these would best describe the unknown liquid ?
A) It contains polar molecules that conduct electricity.
B) The water that the solid is dissolved in conducts electricity.
C) It contains a ionic compound that conducts electricity in solution.
D) It contains a covalent compound that conducts electricity in solution.
ANSWER:
C) It contains a ionic compound that conducts electricity in solution.
for usatestprep YW
Strong Acid: dissolves and dissociates 100% to produce protons (H+) 1. seven strong acids: HCl, HBr, HI, HNO3, H2SO4, HClO4, & HClO3 2. ... Weak Acid: dissolves but less than 100% dissociates to produce protons (H+) 1.