Distinguish between the following d(ekdi/0sic 4terms:

1.Precision and accuracy.
2.Systematic error and random error.

  Which of the following isc:jbk ,+gv5 jn correct?

  A thermometer was used to record the temperature of pure boilc03ij 1t:mnu 4frielsp,/3g0 a j i;iming water at sea level three times and the values w ii4lretmg31pj cu imf3nas ;0 ,i0:/jere : $85.6^{\circ}C$,$85.7^{\circ}C$,$85.5^{\circ}C$.What can be said about the accuracy and precision of these values?

  Which statement best describes the relationship between x and y on xxfj9md (4dx84ym zpq (.kcc pl0i3,:eqx/mvthe graph below?qpdxycf pk( v j8 ,ec4x i4x mmd./x9(:0l3zqm

  For a first order reaction, thea/3ak:x qj6o c relationship between rate and the concentration of a reactant, [Aq6 xa:ao/ jk3c], can be shown using the following equation: rate =k[A].
The data below gives the rate information for the first order reaction that proceeds in the thermal decomposition of reactant A.



1.On the axes above, draw a graph based on the provided data.
2.The effect of time on the concentration of reactant B for a zero-order reaction was plotted on the graph below.


(i)Draw a line of best fit on the graph above.
2.2.Describe the relationship between time and concentration.
Concentration  ----待选择----decreasesincreases  linearly with time

  The relationship between pressure and tem +qt e0en2rgr+perature of a known volume and amount of gas can be described using Gay-Lussac’s law which stat+n rq0t+ e2egres that pressure is directly proportional to temperature.
P∝T
Where P is pressure in Pa, and T is temperature in K.


1.On the axes above, sketch the graph of P∝T.

2.State two features that would need to be added to your sketched graph to turn it into a drawn graph.

3.The proportionality can be shown in an equation by incorporating a constant, k. The equation becomes P=kT, and follows the format of the equation of a straight line.

3.1.State the feature of a straight line that k represents in this context.
3.2.Deduce the y-intercept of the straight line.straight line=  (Pa)

  Solid sodium carbonate reacts with excess nitric a wfvr6,ih2ze :cid of 0.10 mol dm$^{-3}$ as shown in the equation below:
$Na_2CO_3$(s) + 2$HNO_3$(aq)→$H_2O$(l) + $CO_2$(g) + 2$NaNO_3$(aq)
1.State a method to measure the rate of reaction other than measuring the volume of gas collected.
2.1.Sketch a graph to show the volume of gas produced over time.
2.2.Explain the shape of your graph using the collision theory.
$CO_2$ is produced in the reaction; hence, the volume of $CO_2$  ----待选择----increasesdecreases  over time.
3.On the same graph as in part(bi), sketch another line to show the volume of gas collected over time at a concentration of 0.05 mol dm$^{-3}$ of nitric acid and label it as X.
4.Suggest and describe a factor other than the concentration that can affect the rate of the above reaction.

  The enthalpy of neutralization for the reaction between sulfuric acidixn cd:3m+u0 yr1 us4rt 9ch0d and potassium hydroxide can be determined exuxuir1:t3 msc 00+ hd9c ynd4rperimentally.
$H_2SO_4$(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

1.State the complete balanced equation for the reaction p,eyp0u7qzu7gb * jb+ between sulphuric acid and copper (II)qbp0 7gzeb+yp 7* ,uuj oxide.
2.State the complete balanced equation for the reaction between ethanoic acid and potassium carbonate.
3.Outline two ways to monitor the rate of reaction for reaction (b) above.

  The relationship between energy, E, and wavelength, λ, is shown a38xc 5iw:mglg ccording to the cix8mlw5 g:3gequation below.
E=$\frac{hc}{λ}$


Which of the below statements are correct for the graph below representing E=$\frac{hc}{λ}$
?
I. Energy and wavelength are directly proportional
II.The units for the gradient are J m$^{-1}$
III.The y-intercept has the units J

  The feasibility of aresntp7d d0am (riap( 111y,a0 )ljzk reaction proceeding spontaneously can be predicted using the following e1,drr ) 1eadmta(ias0 p 7n kj(p0lzy1quation:
ΔG=−TΔS+ΔH.
Where ΔG is the change in Gibb’s free energy, ΔS is the change in entropy, and ΔH is the change in enthalpy.


1.When ΔG<0, a reaction can be described as spontaneous. Use the graph above to deduce the lowest temperature at which the reaction becomes spontaneous.
Read graph at ΔG=0,  K.
2.Calculate the gradient of the line and state its units.
3.Use your answer to part (b) to deduce the value and correct units for ΔS.
4.Use the graph to determine the value for ΔG when the temperature is raised to 675K.
Extrapolation of the line=  (kJ mol$^{-1}$)
5.Calculate a value for y-intercept=  and state the correct units {kJmol$^{-1}$|kJmol$^{-1}K^{-1}$}.

  The potential of a cell under non-standard conditions can be calcuw 2v2xd2juwavp(e rzz*+8nq 5lated using the Nernw+napv82r22 zjuv5 *q(wzxde st equation:
E=E$^θ$-$\frac{RT}{nF}$lnQ
For the graph below, which components of the equation represent the gradient and the y-intercept?

  The relationship between the concentration o:ezxu( b 6yzk* 0qx;sff a reactant, A, and the time, for a second-order reacti0e:z*xx( ufbyz q;ks 6on can be expressed using the equation below:
$\frac{1}{[A]}$=kt+$\frac{1}{[A]_0}$
Where [A] is the concentration of reactant A,[A] is the initial concentration of reactant $[A]_0$,t is the time in seconds,and k is a constant.


1.Calculate the gradient of the line and state the correct units.The number=  
2.Use the graph to determine $[A]_0$(also known as the initial concentration of A).
$[A]_0$=  mol dm$^{-3}$
3.Determine the time at which the concentration of A is equal to an eighth of its initial concentration.
[A]=  mol m$^{-3}$
(If you were unable to complete parts (a), and (b), you may use k=0.02, and $[A]_0$ =42).

  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?