Identifying Reactions
In the equation Cu + AgNO₃ → Ag + Cu(NO₃)₂, this specific type of reaction occurs when copper (Cu) replaces silver (Ag)
What is a single exchange reaction
To balance a chemical equation without changing the identity of the substances, you may only change these numbers placed in front of the formulas
What are coefficients
This value, 6.02 x 1023, represents the number of particles in exactly one mole of a substance.
What is Avogadro's number
According to the Bronsted-Lowry definition, a base is substance that acts as one of these
What is a proton acceptor
This term refers to the amount of a substance that would be lethal to 50% of a test population
What is LD50
In a reaction, this observable "cloudy" result indicates a chemical change has occurred.
What is a precipitate
To balance the equation for the combustion of propane, C₃H₈ + O₂ → CO₂ + H₂O , this is the coefficient required for Oxygen (O₂)
What is 5
To find the molar mass of CO2, you add the atomic mass of one Carbon atom to the atomic mass of two of these atoms.
What is Oxygen
On the pH scale, this specific number represents a perfectly neutral solution like pure water
What is 7
If a substance has an LD50 of 18 mg/kg, this is the toxic dose for a human weighing 100 kg
What is 1,800 mg
This term describes a reaction where two or more simple substances combine to form a more complex product such as A + B --> AB
This is the correct balanced formula for the product of the synthesis/combination reaction between Sodium (Na) and Chlorine gas (Cl2).
What is 2NaCl
If you have 2 moles of solute dissolved in 4 liters of solution, this is the resulting Molarity (M).
What is 0.5 M
When an acid and a base are mixed in a neutralization reaction, these two common substances are the standard products
What are a salt and water
Based on the ratio in 3Cu + 2Al(NO3)3 --> 2Al + 3Cu(NO3)2 , you need this many atoms of Copper to produce 2 atoms of Aluminum.
What is 3
Unlike a chemical change, this type of change, such as CO2(s) --> CO2(g), alters the form of a substance but not its chemical identity
What is a physical change
In the reaction below, after balancing, this whole number coefficient applies to Calcium (Ca) in the products to keep SO4 even.
Al2(SO4)3 + Ca(OH)2 → Al(OH)3 + CaSO4
What is 3
This is the easiest wat to decrease the molarity (concentration) of a laboratory solution without removing any solute
What is adding solvent (dilution)
Between 0.1 M HCl and 0.0001 M HCl, this one has the lower pH value
What is 0.1 M HCl
(Higher concentration of H+ means lower pH)
Of the following LD50 values - 200mg/kg, 850 mg/kg, and 2000 mg/kg - this one represents the least toxic substance.
What is 2000 mg/kg
In a balanced equation, the Law of Conservation of Mass is satisfied because these specific tiny units of each element are equal on both sides
What are atoms
According to this balanced equation, how many moles of Cu are required to produce 20 mol of Al?
3 Cu (s) + 2 Al(NO3)3 (aq) --> 2 Al (s) + 3 Cu(NO3)2 (aq)
What is 30
To calculate the mass of 4.0 moles of water (H2O), you multiply 4.0 by this molar mass value
What is 18.02 g/mol
If a solution has a pH of 9, it is classified as this type of substance
What is a base (or alkaline)
To find the mass of a single atom of an element, you divide the molar mass by this constant
What is Avogadro's Number