Changes
Describing Chemical Reactions
Random
More Chemical Reactions
Potpourri
100
One of the following is NOT a physical change: splitting wood, melting ice, burning wood or dissolving salt in water.
What is burning wood?
100
In the formula 5CaSO4, this is the number of oxygen atoms.
What is 20?
100

What are the compounds and elements called on the right side of an equation?

Products.

100

What is the number of energy levels for Calcium?

What is four levels?

100
You can balance chemical equations by changing these.
What are coefficients?
200

Which of the following is a physical change?  

Dying hair a permanent color, 

ice melting, 

burning a candle, 

baking a cake.

Ice melting is a physical change.

200
Chemical equations use these instead of words to summarize a reaction.
What are chemical formulas and other symbols?
200

What is the valence number for Aluminum?

The valence of Aluminum is 3.

200

When one substance takes the place of another within a compound.

What is single replacement?

200
This describes a synthesis reaction.
What is two elements combine to form a compound (more complex substance)?
300
This is the definition of matter.
What is anything that has mass and takes up space?
300
These are substances you have at the beginning of a chemical reaction and are listed on the left hand side of the arrow of a chemical equation.
What are reactants?
300

What charge do metal ions usually have?  Positive or negative?

What is positive?

300

This bond consists of cations and anions.  They have a opposite charge attraction.

What is an ionic bond?

300
These are the two types of changes that can occur in matter.
What are physical and chemical changes?
400

Baking soda is placed in vinegar.  The solution begins to foam up and over the beaker.  Is this a chemical or physical change?

What is a chemical change?

400

Diphosphorus Pentoxide

What is the name for P2O5?

400

The charge of group 15 elements.

What is -3?

400
The reaction 2HgO arrow 2Hg + O is an example of this type of reaction.
What is decomposition?
400

These may not be changed on an element when balancing chemical equations.

What are subscripts?

500
Give three examples that a chemical change has taken place.
What is a change in energy (temperature change), color change, change of texture, formation of a precipitate, formation of a gas?
500
Explain why it is necessary to balance chemical equations.
What is because the principle of conservation of mass states that in a chemical reaction, the total mass of the reactants must equal the total mass of the products?
500

Our body needs them for healthy heart and brain function.  They can be positive or negative.

What are ions?

500
This is the ONLY sure evidence for a chemical reaction.
What is the production of a new substance?
500
These two chemical reaction types could be considered opposites.
What are synthesis and decomposition?
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