Distinguish between the followiq- :xx qzs)y5lng terms:
1.Precision and accuracy.
2.Systematic error and random error.

  A student conducted a titratihubv;50ohnir fot 1 2/on experiment. However, instead of rinsing his apparatus with distilled water, he rinses them with tap water only. What is likely the type ofo0o1i bf2 ht n;5/hvur error?

A student is determining t3v 68/b )rmub:vd igaohe rate of the reaction between $MgCO_3$ and HCl. List 3 sources of random errors.

  The diameter of a cylindrical sample was measured using a verniehlq+ :phsu+q8g n9ui6ac 80sbr caliper at three different points along the sample. The diameters measured were: 13.50 mm, 13.51 mm, 13.a suu+:9 sb 80hhcin6ql8q gp+50 mm. The true diameter of the sample is 12.14 mm. What is the likely type of error, and how can the error be reduced?

  The enthalpy of neutralization for the reaction between sulfuric ayms7h c ; n-*oas1dz:dcid and potassium hydroxide can be determm na:1;-csy*zhdosd 7ined experimentally.
$H_2SO_4$(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?