Why things dissolve: polarity, electrolytes and nonelectrolytes
Grade 10 Science Worksheet

Circle the best answer, or write your answer on the line.
A cup holds 1 mol of dissolved sugar and 1 mol of dissolved salt. How many moles of dissolved particles is that, Bo?
A cup holds 0.5 mol of dissolved sugar and 0.25 mol of dissolved salt. How many moles of dissolved particles is that, Esme?
A jug holds 2 mol of dissolved sugar and 0.5 mol of dissolved salt. How many moles of dissolved particles is that, Jun?
In salt water, what are the dissolved particles, Luz?
- Separate Na⁺ and Cl⁻ ions
- Whole NaCl units
- Tiny drops of melted salt
Why can water pull salt apart, Milo?
- Its charged ends attract the ions
- Its heat melts the salt crystal
- It cuts the salt into whole NaCl pieces
What happens to sugar as it dissolves, Noah?
- It melts into syrup
- Its molecules spread apart but stay whole
- Its molecules split into charged ions, like salt
Why does sugar dissolve in water even though it forms no ions, Ren?
- Sugar melts in water
- Sugar is polar enough to attract water
- Sugar does form ions in water
A tester lights brightly in salt water, dimly in circle water and not at all in sugar water. Which holds the most ions, Tala?
- The salt water
- The sugar water
- They hold the same ions
Why does circle water light the tester a little, Zee?
- Water molecules themselves split into many ions in the tap
- It holds a few dissolved ions from minerals
- Dissolved sugar in it forms ions
Baking soda water lights the tester. What does that show, Ari?
- Baking soda melted in the water
- Baking soda forms ions: it is an electrolyte
- Baking soda stays as whole molecules