Why water matters for life: cohesion, adhesion, heat and ice

Grade 9 Science Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Use this

   Read-about card, not to scale. Water moves from the roots to the leaves through xylem tubes. Water leaving the leaves pulls the water column upward. Water molecules cling to each other and to the xylem walls.

2. 1.

   Pia reads that water reaches the top of a 116-meter tree. Which claim and reason explain how water moves up the xylem?

   • Water is pulled up as one column: adhesion links the molecules and cohesion holds them to the xylem walls
   • Water is pulled up as one column: covalent bonds link each molecule to the next in the tube
   • Water is pulled up as one column: nonpolar water slides along the xylem walls without sticking
   • Water is pulled up as one column: cohesion links the molecules and adhesion holds them to the xylem walls
3. 2.

   model data, two towns at the same latitude. Ren compares two towns at the same latitude. Which town has the milder year, and why?

   • The far inland town; the land heats and cools slowly because of its high specific heat
   • The far inland town; the land shields it from the wind off the sea
   • The town near the sea; nearby water heats and cools slowly because of its high specific heat
   • The town near the sea; nearby water heats and cools quickly because of its high specific heat
4. 3.

   Tala reads how ice thickens on a pond. Which claim and reason explain why the ice grows more slowly each day?

   • The ice grows more slowly, because the pond is running out of water
   • The ice grows more slowly, because the ice on top insulates the water below
   • The ice grows more slowly, because new ice is denser and sinks away from the top
   • The ice grows more slowly, because the air warms up each day

5. Use this

   Investigation card. Question: Does a coin hold more water drops on its heads side or its tails side? Changed: which side of the coin faces up. Measured: drops added with a dropper before the dome of water spills. Kept the same: the dropper, the water, the table. Results table: Side | Coin used | Drops before spilling; heads | dime | 14; tails | penny | 20. model data.

6. 4.

   A dome of water on a coin is held by cohesion. Zee reads this class test. How should the test be fixed?

   • Use colder water for the tails side
   • Use the same coin for both sides, so only the side changes
   • Use a bigger dropper on the tails side
   • Count the drops after the water spills, not before

7. Use this

   Investigation card. Question: Does the kind of paper change how high water climbs a dipped strip? Changed: the kind of paper. Measured: how many centimeters the water climbed in 5 minutes. Kept the same: strip width of 2 cm, the cup, the water, the time. Results table: Paper | Dipped depth (cm) | Climb (cm); paper towel | 1 | 7; printer paper | 3 | 3. model data.

8. 5.

   Ari reads a test of water climbing paper strips. What is the flaw in the test?

   • The strips were cut to different widths, so width changed too
   • The time was too short for the water to climb
   • The strips were dipped to different depths, so depth changed too
   • The water should have been warmer for the printer paper

9. Use this

   Investigation card. Question: Which warms more under a lamp, water or sand? Changed: the material. Measured: the temperature rise after 5 minutes. Kept the same: the lamp, its distance, the start temperature. Results table: Material | Mass (g) | Rise (°C); water | 400 | 4; sand | 100 | 12. model data.

10. 6.

    Bo reads a lamp test on water and sand. What is the flaw in the test?

    • The masses differed, so the rises cannot be compared fairly
    • Water has a high specific heat, so it should have warmed more
    • The start temperatures should have been different
    • The lamp should have been closer to the water
11. 7.

    To carry 1,172 calories of heat away from skin, how much sweat must evaporate at 586 calories per gram, and how does the skin change, Jun?

    • 2 g of sweat; the skin cools
    • 0.5 g of sweat; the skin cools
    • 2 g of sweat; the skin warms
    • 586 g of sweat; the skin cools
12. 8.

    A 100 g sample takes in 600 calories and warms 30 °C, Kira reads. Water needs 1 calorie per gram per °C; sand needs about one fifth of that. What is it?

    • Sand: it needs 20 calories per gram per °C
    • Sand: it needs about 0.2 calorie per gram per °C
    • Water: a high specific heat means it warms the most
    • Water: it needs 6 calories per gram per °C
13. 9.

    model data, a pond in winter. Luz reads pond temperatures under the ice. The warmest water, at 4 °C, is at the bottom. Why is the warmest water at the bottom?

    • Water near 4 °C is denser than colder water, so it sinks to the bottom
    • Heat flows down from the ice, so the bottom gets the most heat
    • Hydrogen bonds pull heat down toward the bottom
    • Ice is denser than liquid water, so it sinks and pushes the warm water down
14. 10.

    not to scale. In a thin glass tube, Milo sees the water surface curve up at the walls, not lie flat. Why does the surface curve up?

    • Water is nonpolar, so it slides up the glass walls
    • The glass walls are warmer than the middle of the water
    • Water molecules are attracted to each other more than to the glass walls
    • Water molecules are attracted to the glass walls more than to each other