Regents Chemistry – Flashcards
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What is the same in an isotope and what is different in an isotope?
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Same Protons
Different Neutrons |
What is the nuclear charge of fluorine? |
+ 9
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State two major findings about the atom. |
The atom is mostly empty space. The nucleus is small and positive. |
| Explain how spectral lines are produced, in terms of electrons. |
Electrons fall from the excited to the ground state.
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In a nuclear reaction mass is always “lost”. Explain this loss of mass. |
Mass was converted to energy. |
Calculate the average atomic mass of carbon:
98% 12C and 2% 14C
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| Why would two elements have similar chemical properties? |
Same group. Same Valence electrons. |
| Why does the radius increase as you move down a group? |
More Shells
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| Describe three properties of metals |
good conductor malleable and ductile shiny |
| Describe three properties of nonmetals |
poor conductor brittle dull |
Which elements lose electrons when forming ions? What happens to the radius? |
metals decreases |
Which elements gain electrons when forming ions? What happens to the radius? |
nonmetals increases |
| Name the four types of chemical reactions. |
synthesis decomposition single replacement double replacement |
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Kinetic Energy Increases Potential Energy remains the same |
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Kinetic Energy remains the same Potential Energy Increases |
How is an ionic bond formed, in terms of electrons? |
Electrons are transferred. |
How is a covalent bond formed, in terms of electrons? |
Electrons are shared. |
What makes a bond more polar, in terms of electronegativity? |
Greater difference in electronegativity. |
What makes a covalent bond polar? |
Unequal sharing of electrons. |
What makes a covalent bond nonpolar? |
Equal sharing of electrons. |
Why is a molecule polar? (HINT:SNAP) |
Asymmetrical. |
Why is a molecule nonpolar? (HINT:SNAP) |
Symmetrical. |
Properties of ionic solids. |
High Melting Point Strong forces Conductor only in the liquid phase |
Properties of molecular solids(covalent bonds). |
Low Melting Point Weak forces Poor Conductor |
Properties of metallic solids. |
High Melting Point Strong forces Great Conductor |
What makes a good conductor(in terms of particles)? |
Mobile Particles. |
How do you increase the solubility of a solid in a liquid? |
Raise temperature |
How do you increase the solubility of a gas in a liquid? |
Lower temperature Increase pressure |
State, in terms of molecular polarity, why 1,2-ethanediol is soluble in water. |
It is polar like water “LIKE DISSOLVES LIKE” |
When is a gas most ideal? |
High Temperature & Low Pressure |
What happens to the freezing and boiling point when salt is added to water? |
F.P. decreases B.P. increases |
What is entropy? What phase has the most entropy? |
Disorder of a system. gas |
How do you increase the rate of a reaction? |
Increase temperature Increase concentration Increase surface Area Increase pressure(gas) Add a catalyst |
Why does increasing the temperature increase the rate of a reaction, in terms of the collision theory? |
There are more collisions. |
How does a catalyst increase the rate of a reaction? |
Lowers the activation energy. |
What occurs at equilibrium? |
Rates are EQUAL Concentrations are constant. |
What type of positive ions do acids produce in water? |
Acids: Hydrogen(H+) or hydronium.(H3O+) |
What type of negative ions do bases produce in water? |
Bases: Hydroxide (OH-) |
What is a neutralization reaction? |
Acid + Base à Salt + Water |
What is an electrolyte? Name three substances that are electrolytes. |
Substance that conducts electricity in water. -Acid, Base, Ionic |
What occurs during oxidation? |
Lose electrons (LEO) Oxidation number increases |
What occurs during reduction? |
Gain electrons (GER) Oxidation number decreases
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What is an endothermic reaction? Draw a potential energy diagram for this reaction.
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What is an exothermic reaction? Draw a potential energy diagram for this reaction |
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What is the difference between a voltaic and an electrolytic cell? |
Voltaic is spontaneous and converts chemical to electrical energy
Electrolytic is non-spontaneous and converts electrical to chemical energy.
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What is the purpose of a salt bridge? |
Allow the flow of ions. |
What is the difference between a saturated and unsaturated hydrocarbon in terms of bonding? |
Saturated- all single bonds between C's. Unsaturated- double or triple bond between two C's. |
What is an isomer? |
Same Molecular formula, but different structural formula. |
Identify the type of organic reaction shown. (a.) Br2 + CH4 → CH3Br + HBr (b.) C4H8 + Cl2 → C4H8Cl2
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(a.) Substitution (b. )Addition
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2SO2(g) + O2(g)ßà 2SO3(g) + energy Explain, in terms of LeChatelier’s principle, why the concentration of SO2(g) increases when the temperature is increased.
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Shifts left. |
a. Explain, in terms of attraction, why a substance has a low boiling point.
b. Explain, in terms of attraction, why a substance has a high boiling point. |
a. Weak forces. b. Strong forces |
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A- Reactants B- Heat of Reaction C- Products D- Activation Energy |
