Question

a)sample	weight	net weight	buret, initial	buret, final	net volume	density,Xm	d=Xm-<x>	d^2
1	108.9125	6.2449	0.21	6.19	5.98	1.044	0.003	9.0x10^-6
2	114.7771	5.8649	6.19	12.09	5.90	0.9941	-0.0469	2.2x10^-3
3	121.4513	6.6742	12.09	18.42	6.33	1.054	0.013	1.7x10^-4
4	127.3443	5.893	18.42	24.19	5.77	1.021	-0.02	4.0x10^-4
5	135.6526	8.3083	24.19	32.12	7.93	1.048	0.007	4.9x10^-5
6	141.9447	6.2921	32.12	38.16	6.04	1.042	0.001	1.0x10^-6
7	147.6895	5.7448	38.16	44.13	5.97	0.9623	-0.0787	6.2x10^-3
8	154.5351	6.8456	44.13	50.00	5.87	1.166	0.125	1.6x10^-2

Standard Deviation; data was obtain during lab but im not sure if the rest calculations are correct (Xm, d=Xm-<x>, and d^2) I'm also having a hard time understanding the concept. please answer the following questions and explain, Thank you. a)show your calculations of the standard deviation, s, from d^2. b) reported value and range:_________ % NaCl from handbook______ pg and year______ c)do you have any values in your table for the density of the salt solution that lies outside the range (<Xm>+_ 2s)?. if so list them d)recalculate <Xm>, omitting values that lie outside the range ( this is the density value you should use to find your experimental %NaCl.)

Answer 1

Following is the solution/Answer to Part-a) of the above problem:

Standard Deviation (i.e. of d²) = 6.0 10^-3 = 0.006

Following is the Calculation (for Part-a) ) , in image format.