Distinguish between the follotx,n r 6/osn :u6qfvz*qx:ax +wing terms:
1.Precision and accuracy.
2.Systematic error and random error.

  A student conducted a titration experiment. However, instead of rinsing his appy.m8 .reuu:h iy;8 -vrife-idaratus w. r e r-8ih;fiiv.ud8ue:- yymith distilled water, he rinses them with tap water only. What is likely the type of error?

A student is determining the rate of the reaction l6h3ivw1vb1dvvp 4 ;xlw; )bxbetween $MgCO_3$ and HCl. List 3 sources of random errors.

  The diameter of a cylindrical sabih//vc fz nxhrj,u;-7a (gn9mple was measured using a vernier caliper at three different points along the sample. The diameters measured were: 13.50 mm, 13.51 mm, 13.50 mm. The true diameter of the sample is 12.14 mm. What is the likely type of error, and x r/ n;v-b (,ua7zjfgnc/9hhihow can the error be reduced?

  The enthalpy of neutralization for the reaction between sul e/a+ow l rzpmvv:dw ;m2df9(,furic acid and potassium hydroxide can be determined experimentally. vp ed/+ vwamz9l,m:rod2fw; (
$H_2SO_4$(aq)+2KOH(aq)→$K_2SO_4$(aq)+2$H_2O$(l)
A student recorded the temperature of 20.0 cm$^3$ of 0.500 mold m$^{-3}$ sulfuric acid every minute. At four minutes,25.0cm$^3$ KOH(aq) is added to the solution, stirred immediately, and temperature recorded for another four minutes. The results are represented in the graph below.



1.Calculate the lowest concentration of aqueous KOH that must be used to ensure it is in excess.
n$_{KOH}$=  mol;C$_{KOH}$=  mold m$^{-3}$
2.Use the graph above to estimate a value for the maximum temperature change, ΔT.
ΔT=  °C
3.State one assumption you made in part (b).
4.Identify the anomalous result and suggest a possible type and source of error.
5.In another experiment with the same reactants, the student measured the initial and final temperatures and presented their results below:
Initial Temperature (°C ± 0.1°C) 24.8 25.1 24.9
Final Temperature (°C ± 0.1°C) 26.4 26.6 26.4
5.1.Calculate the average change in temperature (ΔT) giving its percentage uncertainty.
Average=  °C
5.2.Use sections 1 and 2 of the data booklet to calculate the energy released and its uncertainty. You may assume that the only source of uncertainty is from the temperature change.
Energy released (q)=  J

  25.00 cm$^3$ of 0.100 mold m$^{-3}$$HNO_3$ was titrated against 0.200 mold m$^{-3}$$NaOH$.The volumes of NaOH delivered for the three trials 14.00 cm$^3$ ,14.05 cm$^3$ and 14.00 cm$^3$.
Which statement below best describes these results?