How concentrated is it? Comparing solutions

Answer Key - Grade 8 Science Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. 1.

   Beaker A has 40 dots in 150 mL. Ari wants 10 dots per 100 mL. How many mL of water must be added?

   250 mL
2. 2.

   Beaker B has 30 dots in 120 mL. Bo wants 15 dots per 100 mL. How many mL of water must be added?

   80 mL
3. 3.

   Esme's beaker has 60 dots in 300 mL. To reach 12 dots per 100 mL, how many mL of water must be added?

   200 mL
4. 4.

   Kira mixes 100 mL with 4 dots per 100 mL and 100 mL with 8 dots per 100 mL. What is the mix's concentration?

   • 4 dots per 100 mL
   • 6 dots per 100 mL
   • 8 dots per 100 mL
   • 12 dots per 100 mL
5. 5.

   Luz mixes a strong solution with a weak one. Where does the mix's concentration land?

   • Above the stronger one
   • Exactly at zero
   • Below the weaker one
   • Between the two
6. 6.

   Milo says a big pot of soup must be saltier than a small bowl, because it holds more salt. Agree or disagree?

   • Agree: a bigger pot is stronger
   • Agree: more salt means saltier
   • Disagree: soup has no salt
   • Disagree: compare salt per 100 mL
7. 7.

   Noah says pouring half a glass of sugar water away makes the rest twice as concentrated. Agree or disagree?

   • Disagree: it stays the same
   • Disagree: it becomes pure water
   • Agree: less water means stronger
   • Agree: half the sugar is left, so weaker
8. 8.

   Beaker A has 9 dots in 300 mL and beaker B has 4 dots in 100 mL. Pia says A is more concentrated. Agree or disagree?

   • Agree: A has more liquid
   • Disagree: B has more per 100 mL
   • Disagree: they are the same
   • Agree: A has more dots
9. 9.

   Two beakers each have 6 dots per 100 mL. Tala mixes them. Which drawing shows the mix?

   • 6 dots in 300 mL
   • 18 dots in 100 mL
   • 18 dots in 300 mL
   • 12 dots in 300 mL
10. 10.

    Zee mixes 200 mL at 3 dots per 100 mL with 200 mL at 9 dots per 100 mL. What is the mix's concentration?

    • 9 dots per 100 mL
    • 3 dots per 100 mL
    • 12 dots per 100 mL
    • 6 dots per 100 mL