Unit 1 Test Review Elements and Compounds

Elements

Compounds are pure substances. What other substances are considered pure substances? Chemical reactions Elements Mixtures Solutions

Apron

A student combines a liquid and a solid in a beaker. The mixture then rapidly bubbles and overflows the beaker. The student is wearing goggles and gloves at the time. What other piece of safety equipment should the student wear? Tongs Apron Fire Blanket None of the above

N

The chemical symbol for nitrogen is — Na Ni Ne N

H2

The following is a chemical equation that represents the law of conservation of mass. 8 CO + 17 H2 ------> C8H18 + 8 H2O Which substance in the above equation is represented by an element?

B. wearing loose clothing and jewelry

The sixth grade science students are conducting an investigation of the possible creation of new substances. They will be working with a partner in the lab mixing chemicals according to the teacher's directions. Which of the following is considered an unsafe lab practice? A. tying back long hair B. wearing loose clothing and jewelry C. wearing goggles, apron, and gloves D. wearing closed-toe shoes

D two compounds

The two products to the right of the arrow in the chemical equation above are best classified as — A one compound and one element B two elements C one element and two compounds D two compounds

C. Water is a pure substance and a compound.

Water has the chemical formula H2O. Which statement correctly describes water? A. Water is not a pure substance, but is an element. B. Water is a pure substance and an element. C. Water is a pure substance and a compound. D. Water is not a pure substance, but is a compound.

Copper - Cu

Which of the following correctly represents an element? Water - H2O Copper - Cu Carbon monoxide - CO Salt - NaCl

1 and 3

Which of the following do NOT describe an element? 1. A Mixture of different chemicals 2. Represented by a symbol that contains one uppercase letter 3. Represented by a symbol that can contain a second uppercase letter 4. Represented by a symbol that can contain a lower case letter 5. A pure substance 6. Can be identified using a periodic table

CO

Which of the following is a compound? Co Fe H CO

He

Which of the following is an element? He CaCl2 H2SO4 NaCl

NH3

Which of the following substances is a compound? C NH3 Co K

Co

Which of the following substances is an element? CO2 NaS Co KF

2, 3, 5, and 6

Which of the following substances represents a compound? 1. Cr 2. KF 3. H2SO4 4. Cs 5. Al2O3 6. CaO

2, 5, and 6

Which of the following substances represents an element? 1. CO 2. Ag 3. HI 4. CN- 5. Db 6. Xe

II and III

Which of the following would be found ONLY in the Compounds side of an Element and Compounds Venn diagram? I. Is a pure substance II. Made from more than one element III. Formed through a chemical reaction IV. Found on a periodic table V. Essential for life VI. Found on Earth

IV

Which of the following would be found ONLY in the Elements side of an Element and Compounds Venn diagram? I. Is a pure substance II. Made from more than one element III. Formed through a chemical reaction IV. Found on a periodic table V. Essential for life VI. Found on Earth

I, V, VI

Which of the following would be found in the middle of an Element and Compounds Venn diagram? I. Is a pure substance II. Made from more than one element III. Formed through a chemical reaction IV. Found on a periodic table V. Essential for life VI. Found on Earth