Elements
Which of the following is NOT an element?
A. Lead(Pb)
B. Carbon(C)
C. Mercury(Hg)
D. Salt(NaCl)
D. Salt(NaCl)
Carbonic acid calcium salt(CaCO3) is an odorless, tasteless powder or crystal that occurs in nature. How many elements does this compound have?
3
True/false
When a chemical change takes place, the substance does not change at all.
False
True/False
A physical change is when the original substance changes into a new substance.
False
List three examples of an element that are NOT on your review.
Answers vary.
Which of the following substances represents an element?
Ag, HI, Xe, CN-, CO, Db
A. CN-,HI,CO
B. Ag,HI,Db,CN-
C. Ag, Xe, Db
D. CN-,HI,CO,Db
C. Ag, Xe, Db
A pure substance made of 2 or more elements combined and is represented by a chemical formula
True/False
The following examples are all chemical changes:
1. Dying your hair
2. Spoiling food
3. Exploding fireworks
True
True/False
Are the following all examples of a physical change?
1. Squeezing oranges for juice
2. Mowing the lawn
3. Boiling water
True
List three examples of a compound that are NOT found on your review.
Answers vary.
Characteristics of an element
A pure substance found on the periodic table represented by a chemical symbol.
Compounds are pure substances. What other substances are considered pure substances?
A. Chemical reactions
B. Elements
C. Mitures
D. Solutions
B. Elements
A. The temperature changes
B. A gas is produced
C. A solid is formed
D. One substance dissolves into another substance
D. One substance dissolves into another substance
When a substance changes from a solid to a liquid, is that a chemical change or a physical change?
Physical change
Name three observations one might see when mixing baking soda and vinegar
Bubbles forming
A gas is produced
Temperature change
Which of the following most closely represents what it means to be an element?
A. A bowl of ice cream with a scoop of strawberry, a scoop of vanilla, and a scoop of chocolate.
B. A package of skittles
C. A package of M&Ms
D. A package of Juicy Fruit gum
D. A package of Juicy Fruit gum
Which of the following best used to demonstrate the differences between elements and compounds?
A. An element is like an airport and the compound is like the Mcdonald’s there.
B. An element is like the zoo and the compound is like an animal living there
C. An element is like a hamburger bun and the compound is the hamburger
D. An element is like a sandcastle and the compound is the sand.
C. An element is like a hamburger bun and the compound is like the hamburger.
When baking a cake, there are several ingredients that one must use. Eggs, flour, sugar and oil and cocoa are all mixed together and placed in the oven to bake. After baking, the cake looks different than the original ingredients. Why did the ingredients change.
The ingredients were cooked and the substance changed from raw to baked, therefore a chemical change took place.
Two liquids are mixed together. Which of the following does NOT identify the formation of a new substance?
A. A gas is produced
B. One liquid dissolves into another
C. The temperature changes
D. A solid is formed.
List three examples of a physical and chemical change NOT found on your review.
Answers vary.
The smallest part of an element?
A. Molecule
B. Atom
C. Mixture
D. Solution
Atom
Why are properties of a compound different than the elements that make it up?
After an investigation, students were disposing o leftover substances. One student poured all of the liquid down the sink drain. A few seconds later, a white cloud formed above the sink, and the students eyes began to burn. Which best describes the occurence?
A. The student did not wait two minutes in between pouring each liquid down the drain
B. The student did not allow water to run in the sink after pouring each liquid down the drain
C. A physical change occurred resulting in the formation of a new substance
D. A chemical change occurred resulting in the formation of a new substance
D. A chemical change occurred resulting in the formation of a new substance
Explain the difference between a chemical change and a physical change
A physical change is when the substance does NOT change into something new, just the form or its appearance changes.
A chemical change is when the substance DOES change into something new with new properties.
Cr(NH3)6(NO3)3 is
A. Element
B. Compound
If a compound, how many elements are there and what are the elements?
B. Compound
There are 4 elements in the compound:
Chromium, Nitrogen, Hydorgen, and Oxygen