Unit 2 test flashcards
Exothermic or endothermic? Burning wood.
exothermic
Covalent bonds form between…
non-metals
What type of chemical reaction occurs when 1 substance breaks down into 2 or more substances?
decomposition
Requires energy, Endothermic, Delta H is positive
Requires energy, Endothermic, Delta H is positive
What type of chemical reaction occurs when two compounds swap partners?
Double Replacement
What type of chemical reaction occurs when 2 or more substances combine to form another?
synthesis
Exothermic or endothermic? Baking a cake.
endothermic
How can you tell if a reaction is endothermic?
the temperature decreases
What type of energy is released during the fusion or fission of atoms?
nuclear
Ionic bonds always form between metals and ___________.
non-metals
What is a half-life (in science)?
the amount of time for half a radioactive sample to decay
Covalent drawings use…
circles
When drawing an ionic compound draw the
lewis structures & transfer with arrow and add charges
What is nuclear fusion?
combining 2 small atoms into 1
What is a concern about nuclear energy?
nuclear radioactive waste exposure which can be fatal to living things
What type of chemical reaction occurs when 1 element replaces another?
Single Replacement
Covalent Bonds
share
Do endothermic reactions produce or absorb energy?
absorb
Is this equation balanced? Li + O2 → Li2O
no
Is this equation balanced? PbO2 → PbO + O2
no
What does a catalyst do?(Science question)
makes a chemical reaction faster
What is half life?
time for half the nuclei to decay
Is this equation balanced? LiCl + Na → Li + NaCl
yes
Is this equation balanced? 2NaCl + MgO → MgCl2 + Na2O
yes
What type of reaction is: Mg + O2 → MgO
sythesis
Law of conservation of mass
mass of reactants = mass of products
What type of reaction is O2 + CH3OH → H2O + CO2
combustion
What type of reaction is NaOH + H2SO4 → Na2SO4 + H2O
Double Replacement
What is a coefficient?
the big number in front of an element/compound
Reactions with only one reactant are…
decomposition
Exothermic reactions…
release heat
What coefficient should go in the blank: 1PCl5 + 4H2O → ___HCl + H3PO4
5
What coefficient should go in the blank: Na2CO3 + ___HCl → 2NaCl + H2O + CO2
2
Which is NOT a sign of a chemical reaction?
dissolving
FISSION OR FUSION: Can generate most energy
fusion
