Unit 1 Review-1 PDF Practice Exercises

# Skill Building Topic 4: Significant Figures - Practice Exercise ## **Complete each of the following exercises.** 1. **How many significant figures are in each of the following?** * a. 451 000 m * b. 6.626 x 10²³ J s * c. 0.0065 g * d. 4056 V * e. 0.0540 mL 2. **Fo...

# Skill Building Topic 4: Significant Figures - Practice Exercise ## **Complete each of the following exercises.** 1. **How many significant figures are in each of the following?** * a. 451 000 m * b. 6.626 x 10²³ J s * c. 0.0065 g * d. 4056 V * e. 0.0540 mL 2. **For the centimeter rulers below record the length of the arrow shown.** - The image shows two horizontal ruler lines, each with numerical markings above that go from 7-11. - Above the first ruler, there is an arrow pointing towards 10. - Above the second ruler, there is an arrow pointing between 9 and 10, but closer to 10. * a. 10 cm * b. 9.8 cm ## Answer the following problems using the correct number of significant figures. 3. * a. 16.27 + 0.463 + 32.1 = 50.8 * b. 42.05 - 3.6 = 38.5 * c. 15.1 x 0.032 = 15.1 x 10^-2 * d. 13.36 / 0.0468 = 285 ## **Name: ** ## **Date:** ## **Class Period:** ## **Student ID:** # Chemistry - Unit 4 Worksheet 1 ## 1. Identify the separation techniques pictured below . Which technique would be useful to separate a mixture of sand and salt? Of salt and water? - The image depicts two common separation techniques. - The first image shows a funnel with a filter paper inside, pouring something into a container of liquid beneath the funnel. - This is **filtration**. - This technique would be useful for separating a mixture of sand and salt, as the sand would be caught in the filter paper and only the salt would go through. - The second image shows a round-bottom flask with a tube extending upward and bending in the middle. Liquid is pouring out of the flask and into a different container. - This is **distillation**. - This technique would be useful for separating a mixture of salt and water. The water would be evaporated, condense in the tube, and be captured by the container at the end of the tube, leaving the salt in the flask. ## 2. Explain why the technique at left would not be effective in separating a mixture of salt and sugar. - **Filtration** would not be an effective technique for separating salt and sugar because both materials are **soluble** and would pass through the filter paper along with the solvent. ## 3. Draw Particle Representations for the following: - The image includes a table with two boxes. Above each box is a label: - A mixture of iron and sulfur. - A compound of iron and sulfur. - The top of each box is labeled: Substance. - Underneath that, the image shows a table with a description under two additional columns: - **Particle Representation:** - **Properties:** - You would have to describe the particle representation of each substance. - For example, you could say: *Imagine a box filled with iron atoms that are black and sulfur atoms that are yellow. The iron atoms are clustered together in one area of the box. The sulfur atoms are clustered together in another area of the box. Iron atoms are attracted to magnets. The sulfur atoms are not attracted to magnets.* - Then, you would describe the properties of the substance. ## 4. Explain why a magnet can separate iron atoms from the mixture but not from the compound. - **Iron** is a **ferromagnetic** material, meaning it is strongly attracted to magnets. **Sulfur** is **diamagnetic**, meaning it is not attracted to magnets. If you were to mix iron and sulfur, a magnet could be used to separate the iron from the mixture. - **Iron sulfide** is a compound. In order to form this, iron and sulfur react, changing the composition of the atoms - you cannot easily separate them again. ## 5. Consider the four containers below: - Image shows four containers with an assortment of circles inside, where some are black and some are white. - Each container is labeled A, B, C, and D. * a. Which of these are mixtures? _A, C_ , pure substances? _B, D_ * b. Which contain only compounds? _ _ , only elements? _ _ ## 6. Consider the four containers below: - Image shows four containers with an assortment of circles inside, where some are black and some are white. - Each container is labeled A, B, C, and D. * a. Which of these are mixtures? _C, D _, pure substances? _A, B_ * b. Which contain only compounds? _ _ , only elements? _ _ ## 7. Consider the four containers below: - Image shows four containers with an assortment of circles inside. Some containers have only black circles, some have only white circles, some have black AND white circles. - Each container is labeled A, B, C, and D. * a. Which of these are mixtures? _C, D _, pure substances? _A, B_ * b. Which contain only compounds? _ _ , only elements? _A, B_, ## 8. Which of the containers in #7 contain a gas? _ _ , a liquid _ _ , a solid _ _ ## Name: ## Date: ## Pd: # Chemistry - Unit 4 Worksheet 1 ## 1. Identify the separation techniques pictured below. Which technique would be useful to separate a mixture of sand and salt? Of salt and water? - The image depicts two common separation techniques. - The first image shows a funnel with a filter paper inside, pouring something into a container of liquid beneath the funnel. - This is **filtration**. - This technique would be useful for separating a mixture of sand and salt, as the sand would be caught in the filter paper and only the salt would go through. - The second image shows a round-bottom flask with a tube extending upward and bending in the middle. Liquid is pouring out of the flask and into a different container. - This is **distillation**. - This technique would be useful for separating a mixture of salt and water. The water would be evaporated, condense in the tube, and be captured by the container at the end of the tube, leaving the salt in the flask. ## 2. Explain why the technique at left would not be effective in separating a mixture of salt and sugar. - **Filtration** would not be an effective technique for separating salt and sugar because both materials are **soluble** and would pass through the filter paper along with the solvent. ## 3. Draw Particle Representations for the following: - The image includes a table with two boxes. Above each box is a label: - A mixture of iron and sulfur. - A compound of iron and sulfur. - The top of each box is labeled: Substance. - Underneath that, the image shows a table with a description under two additional columns: - **Particle Representation:** - **Properties:** - You would have to describe the particle representation of each substance. - For example, you could say: *Imagine a box filled with iron atoms that are black and sulfur atoms that are yellow. The iron atoms are clustered together in one area of the box. The sulfur atoms are clustered together in another area of the box. Iron atoms are attracted to magnets. The sulfur atoms are not attracted to magnets.* - Then, you would describe the properties of the substance. ## 4. Explain why a magnet can separate iron atoms from the mixture but not from the compound. - **Iron** is a **ferromagnetic** material, meaning it is strongly attracted to magnets. **Sulfur** is **diamagnetic**, meaning it is not attracted to magnets. If you were to mix iron and sulfur, a magnet could be used to separate the iron from the mixture. - **Iron sulfide** is a compound. In order to form this, iron and sulfur react, changing the composition of the atoms - you cannot easily separate them again. ## 5. Consider the four containers below: - Image shows four containers with an assortment of circles inside, where some are black and some are white. - Each container is labeled A, B, C, and D. * a. Which of these are mixtures? _A, C_ , pure substances? _B, D_ * b. Which contain only compounds? _ _ , only elements? _ _ ## 6. Consider the four containers below: - Image shows four containers with an assortment of circles inside, where some are black and some are white. - Each container is labeled A, B, C, and D. * a. Which of these are mixtures? _C, D _, pure substances? _A, B_ * b. Which contain only compounds? _ _ , only elements? _ _ ## 7. Consider the four containers below: - Image shows four containers with an assortment of circles inside. Some containers have only black circles, some have only white circles, some have black AND white circles. - Each container is labeled A, B, C, and D. * a. Which of these are mixtures? _C, D _, pure substances? _A, B_ * b. Which contain only compounds? _ _ , only elements? _A, B_, ## 8. Which of the containers in #7 contain a gas? _ _ , a liquid _ _ , a solid _ _