classification of matter ws 1\ninstructions: for each of the following examples, classify it as a…

Explanation:

Step1: Recall definitions

An element is a pure - substance made of only one type of atom. A compound is a pure - substance made of two or more different types of atoms chemically combined. A homogeneous mixture has a uniform composition throughout, and a heterogeneous mixture has a non - uniform composition.

Step2: Analyze each substance

1. Au (Gold): It is an element, so the answer is E.
2. Saltwater: It is a mixture of salt and water with a uniform composition, so it is a homogeneous mixture (HO).
3. Oil and vinegar salad dressing: Oil and vinegar do not mix uniformly, so it is a heterogeneous mixture (HE).
4. Iron (Fe): It is an element, so the answer is E.
5. Sugar ($C_{12}H_{22}O_{11}$): It is a compound made of carbon, hydrogen, and oxygen atoms chemically combined, so the answer is C.
6. Salad: It has a non - uniform composition with different components like vegetables, so it is a heterogeneous mixture (HE).
7. Brass (an alloy of copper and zinc): It has a uniform composition, so it is a homogeneous mixture (HO).
8. Distilled water ($H_2O$): It is a compound made of hydrogen and oxygen atoms chemically combined, so the answer is C.
9. Concrete: It has a non - uniform composition with different aggregates, so it is a heterogeneous mixture (HE).
10. Gold (Au): It is an element, so the answer is E.
11. Smoke: It is a heterogeneous mixture of solid particles in air.
12. Steel (an alloy): It has a uniform composition, so it is a homogeneous mixture (HO).
13. Carbon dioxide ($CO_2$): It is a compound made of carbon and oxygen atoms chemically combined, so the answer is C.
14. Soda (carbonated drink): It is a homogeneous mixture of carbon dioxide and other substances in water.
15. Soil: It has a non - uniform composition with different particles, so it is a heterogeneous mixture (HE).
16. A mixture of sand and salt: It has a non - uniform composition, so it is a heterogeneous mixture (HE).
17. Vinegar (acetic acid in water): It has a uniform composition, so it is a homogeneous mixture (HO).
18. Mercury (Hg): It is an element, so the answer is E.
19. Chocolate chip cookies: It has a non - uniform composition with chocolate chips and dough, so it is a heterogeneous mixture (HE).
20. Pure oxygen ($O_2$): It is an element, so the answer is E.
21. Orange juice: If it has no pulp, it is a homogeneous mixture (HO).
22. Table salt (sodium chloride, $NaCl$): It is a compound made of sodium and chlorine atoms chemically combined, so the answer is C.
23. Iron oxide (rust, $Fe_2O_3$): It is a compound made of iron and oxygen atoms chemically combined, so the answer is C.
24. Tea (with no solids): It is a homogeneous mixture (HO).
25. Pebbles in water: It has a non - uniform composition, so it is a heterogeneous mixture (HE).
26. Milk: It is a homogeneous mixture (HO).
27. Blood: It is a heterogeneous mixture with different components like cells and plasma.
28. Air freshener spray: It is a homogeneous mixture (HO).
29. Cereal in milk: It has a non - uniform composition, so it is a heterogeneous mixture (HE).
30. Carbonated water: It is a homogeneous mixture (HO).
31. Crude oil: It is a homogeneous mixture (HO).
32. Limestone ($CaCO_3$): It is a compound made of calcium, carbon, and oxygen atoms chemically combined, so the answer is C.
33. Paint: It is a homogeneous mixture.
34. Lemonade (with no pulp): It is a homogeneous mixture (HO).
35. Baking soda (sodium bicarbonate, $NaHCO_3$): It is a compound made of sodium, hydrogen, carbon, and oxygen atoms chemically combined, so the answer is C.
36. Unpopped popcorn kernels: It is a heterogeneous mixture (HE).
37. Zn (zinc): It is an element, so the answer is E.
38. Alkaline batteries (a mixture of solids): It is a heterogeneous mixture (HE).
39. Muddy water: It has a non - uniform composition, so it is a heterogeneous mixture (HE).
40. Pure silver (Ag): It is an element, so the answer is E.

Answer:

1. E
2. HO
3. HE
4. E
5. C
6. HE
7. HO
8. C
9. HE
10. E
11. HE
12. HO
13. C
14. HO
15. HE
16. HE
17. HO
18. E
19. HE
20. E
21. HO
22. C
23. C
24. HO
25. HE
26. HO
27. HE
28. HO
29. HE
30. HO
31. HO
32. C
33. HO
34. HO
35. C
36. HE
37. E
38. HE
39. HE
40. E