period 1 – task 1 (1)title and hypothesis. kumara chips and salt hypothesis: kumara chips placed...
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Period 1 – Task 1Period 1 – Task 1
(1) Title and Hypothesis
Kumara Chips and SaltKumara Chips and Salt
Hypothesis:Kumara Chips placed in solution with high
concentrations of salt (0.6 mol L-1 and 0.8 mol L-1), will lose mass as the chips will lose water due to osmosis. Kumara chips placed in solution with lower concentrations of salt (distilled water, 0.2 mol L-1 and 0.4 mol L-1) will gain mass as the chips will gain water due to osmosis.
Marking (A/M/E):
Purpose stating what will happen to the chips in respect to osmosis.
(2)The range over which the independent variable will be changed
(3)How the dependent variable will be measured
(4)The control solution you will use(5)How you will control or measure other
variables or factors that could have a significant impact on your investigation
(6)How you will ensure your results accurate, valid and reliable
Independent Variable:Concentration of Salt solutions (0.2 mol L-1; 0.4 mol L-1, 0.6 mol L-1, 0.8 mol L-1)
Dependent Variable:Change in mass of kumara chips in grams.
Control:Distilled water
Controlled Variables:- use the same kumara (to ensure water content is the same for all chips)- remove skin (to keep the chemicals the same)- same size and shape of chips (to keep surface area to volume ratio the same)- volume of solution ( _____ mL)- time the chips are kept in the solution ( _____ hours)- covered containers (to stop evaporation)- keep all containers in the same cupboard (to keep temperature and other conditions the same)- blotting dry before weighing (to remove excess water)- same electronic scales
Accuracy, validity and reliability:- repeats- checking of calculations and weighing- control of variables
(7) Method
Method:(1) Collect distilled water and salt solutions (0.2 mol L-1;
0.4 mol L-1, 0.6 mol L-1, 0.8 mol L-1)(2) Fill three of the plastic containers with _____ mL of the 0.2
mol L-1 solution. Clearly label each container with 0.2 and A, B and C.
(3) Repeat with all the other solutions and the distilled water.(4) Cut 15 kumara chips from the same kumara using the _____
sized cork borer. Cut each chip to _____ cm in length.(5) Blot each chip with a paper towel.(6) Weigh each chip and place each one in each of the plastic
containers. Record the weight of the chip and the plastic container it has been placed in.
(7) Put the lid on each of the plastic container.(8) Place all the containers on the same place on the back bench
so they all experience the same changes in temperature.(9) Leave all the chips in the solution until next period ( _____
hours)(10) Remove each chip, blot it dry with a paper towel and reweigh
it. Record the final weight against each of the plastic containers. Use the same electronic scales to ensure consistency.
(11) Work out percentage mass change using the formula: difference in weight original weight
X 100
(8) Trial to fill in your blanks
Controlled Variables:- use the same kumara (to ensure water content is the same for all chips)- remove skin (to keep the chemicals the same)- same size and shape of chips (to keep surface area to volume ratio the same)- volume of solution ( _____ mL)- time the chips are kept in the solution ( _____ hours)- covered containers (to stop evaporation)- keep all containers in the same cupboard (to keep temperature and other conditions the same)- blotting dry before weighing (to remove excess water)- same electronic scales
Accuracy, validity and reliability:- repeats- checking of calculations and weighing- control of variables
Method:(1) Collect distilled water and salt solutions (0.2 mol L-1;
0.4 mol L-1, 0.6 mol L-1, 0.8 mol L-1)(2) Fill three of the plastic containers with _____ mL of the 0.2
mol L-1 solution. Clearly label each container with 0.2 and A, B and C.
(3) Repeat with all the other solutions and the distilled water.(4) Cut 15 kumara chips from the same kumara using the _____
sized cork borer.(5) Blot each chip with a paper towel.(6) Weigh each chip and place each one in each of the plastic
containers. Record the weight of the chip and the plastic container it has been placed in.
(7) Put the lid on each of the plastic container.(8) Place all the containers on the same place on the back bench
so they all experience the same changes in temperature.(9) Leave all the chips in the solution until next period ( _____
hours)(10) Remove each chip, blot it dry with a paper towel and reweigh
it. Record the final weight against each of the plastic containers. Use the same electronic scales to ensure consistency.
(11) Work out percentage mass change using the formula: difference in weight original weight
X 100
Method:(1) Collect distilled water and salt solutions (0.2 mol L-1;
0.4 mol L-1, 0.6 mol L-1, 0.8 mol L-1)(2) Fill three of the plastic containers with _____ mL of the 0.2
mol L-1 solution. Clearly label each container with 0.2 and A, B and C.
(3) Repeat with all the other solutions and the distilled water.(4) Cut 15 kumara chips from the same kumara using the _____
sized cork borer.(5) Blot each chip with a paper towel.(6) Weigh each chip and place each one in each of the plastic
containers. Record the weight of the chip and the plastic container it has been placed in.
(7) Put the lid on each of the plastic container.(8) Place all the containers on the same place on the back bench
so they all experience the same changes in temperature.(9) Leave all the chips in the solution until next period ( _____
hours)(10) Remove each chip, blot it dry with a paper towel and reweigh
it. Record the final weight against each of the plastic containers. Use the same electronic scales to ensure consistency.
(11) Work out percentage mass change using the formula: difference in weight original weight
X 100
Marking (M/E)A method includes:
valid range IV - five conc including distilled water plus 0.3 mol L-1 or below and above 0.3 mol L-
1 (step 1);DV – mass of chips before (step 6) & after (step 10);Repeats (step 2 & 4)OV - volume of solution (step 2), same kumara (step 4), same shape/size chips (step 4), blotting dry before weighing (steps 5 & 10), cover to stop evaporation (step 7), stated time (step 9), same temperature (step 8), same scales (step 10).