Asample of sodium chloride (nacl) has a mass of 17.45 g. a) calculate the number of moles of nacl in the sample. show your work. b) calculate the number of moles of each element (number of moles of na and number of moles of cl) in nacl in the sample. use your answer from part a as a starting point. show your work. i’m struggling a little bit with how to approach this problem and solve it. could someone me out? : )

Part A: Given mass of NaCl * 1mol of NaCl/molar mass of NaCl = # of moles

17.45 g NaCl * 1 mole of NaCl /58.44 g NaCl = 0.298 moles of NaCl

Part B: First, let’s start with sodium, Na. To find the given mass of sodium, divide the given mass of NaCl (17.45)/the molar mass of NaCl(58.44) and multiply that by the molar mass of Na(22.99) to get the given mass of Na.

Given mass of Na * 1mol of Na/molar mass of Na= # of moles of Na.  

6.864* 1mol Na/22.99 g Na=0.298 moles of sodium.

Repeat the above steps with chlorine.  

Given mass of Na or Cl*1mol of Cl/molar mass of Cl = # of moles Cl.  

10.58* 1mol Cl/ 35.45 g of Cl= 0.298 moles of chlorine.

I wish you well on the rest and let me know of you need any more help by messaging me on .

Good Luck :)

Btw sry for answering so late.

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.