Atomic Anatomy
Helium has an atomic number of 2 because it has 2 of these positively charged subatomic particles in its nucleus.
What are protons?
True or False: Dissolving salt or sugar in water is considered a chemical reaction.
What is False (it is a physical change)?
These starting materials found on the left side of a chemical equation react together.
What are reactants?
The Law of Conservation of Mass states that during a chemical reaction, mass is neither created nor this.
What is destroyed?
A chemical reaction that releases thermal energy and causes the temperature of its surroundings to rise is called this.
What is exothermic
These negatively charged subatomic particles orbit the nucleus of an atom.
What are electrons?
This is the fundamental difference between a chemical change and a physical change.
What is a new substance is formed in a chemical change (and no new substance is formed in a physical change)?
These ending materials are found on the right side of a chemical equation after a reaction takes place.
What are products?
In the decomposition of water (2H2O --> O2 + 2H2), if there are 6 total atoms in the reactants, there must be this many total atoms in the products.
What is 6?
Cellular respiration releases energy for living organisms to use, making it an example of this type of reaction.
What is an exothermic reaction?
In the chemical formula Na2H2, this is the total number of hydrogen atoms present.
What is 2?
Which of these is a chemical change?
A) Cutting paper into 12 pieces
B) Lightly charring toast in a toaster
C) Chocolate syrup dissolving in milk
B) Lightly charring toast in a toaster?
This term describes the solid that forms and settles out when two liquid solutions react together.
What is a precipitate?
In the equation CaCO3 --> CaO + CO2, the reactant side has 5 atoms 1 Ca, 1 C, 3O. The product side has this many MORE atoms than the reactant side.
What is 0 (they have the exact same number of atoms)?
Adding heat to a chemical reaction usually causes the rate of the reaction to move at this speed.
What is faster?
Substances like O3 (ozone) or Cl2 (chlorine gas) consist of bound identical atoms, making them simple molecules, but NOT this.
What is a compound?
When iron rusts outside after reacting with water and oxygen, its color changes from silvery gray to dark orange because rust is a brand-new substance with different these.
What are properties?
This visible clue in an open beaker indicates that a gas is being produced during a chemical reaction.
What is bubbling.
If you react 71g of CuSO4 with 25g of Iron Fe, the total combined mass of the products FeSO4 + Cu will equal this many grams.
What is 96 grams 71g + 25g
This special type of substance can be added to a chemical reaction to speed it up without being consumed itself.
What is a catalyst?
In a balanced chemical equation, this is the only number you are allowed to change to balance the equation—never the subscripts!
What are coefficients?
During a chemical reaction, the atoms of the reactants do NOT disappear or multiply; instead, they do these three things to form new products.
What is unbond, rearrange, and rebond?
In an investigation mixing two colorless liquids AgNO3 and KCl, a student observed a white solid form. This proved a chemical reaction occurred because the products had different states of matter and different properties than these.
What are the reactants?
In an experiment, the mass inside an open beaker dropped from 166.1g to 164.7g. Mass wasn't destroyed; it decreased because this escaped into the air.
What is gas (bubbles)
On a molecular level, explain why a warm glowstick glows brighter than a cold glowstick.
What is higher temperature makes molecules move faster and collide more frequently/with more energy, speeding up the reaction rate?