in the gold foil experiment, more than 99% of the alpha particles passed thorough the gold foil with little or no deflection. As a result, Rutherford concluded that most of the volume of each gold atom was empty space.

Protons and neutrons are located int he nucleus of any atom, carbon included. Electrons are located outside the nucleus.

The proton is the only positive particle in an atom. It is located in the nucleus. Neutrons are neutral, with a zero charge also located in the nucleus. Electrons are negatively charged and are located outside the nucleus in orbitals.

A neutron has approximately the same mass as a proton.

Diamond and graphite has different molecular structures. Therefore they have different chemical and physical properties.

– image from http://www.ptable.com

Metalloids are B, Si, Ge, As, Sb, Te, Po, and At.

Al is the ONLY element that touches the line in your Reference Table that is a metal, all others are metalloids.

Metals can be found below the line – Al, Ga, In, Ti, Sn, Pb, Bi, etc (to the left of the line).
Non-metals can be found above the line or to the right – C, N, P, O, S, Se, Br, I, etc.

As electrons in an excited state move to a lower energy levels, the release of energy in the form of electromagnetic radiation (light).

An atom’s attraction for electrons in a chemical bond is measured by its electronegativity. As the electronegativity increases, the attraction for electrons also increases. See Reference Table S for electronegativity values.

Molecules with polar bonds will be polar if their bonds lack symmetry.

Compounds may be classified according to the bonding of the atoms within a compound. if the atoms are ions, the compound is classified as ionic. If the bonds are covalent the compound is classified as molecular.

Refer to the Periodic Table of Elements. Cobalt, Co atomic number 27, is a transition element and is therefore metallic.

Sublimation is the phase change from solid to gas. The reverse process from gas to solid is called deposition.

Solid to liquid – melting

Liquid to gas – evaporation

Gas to Liquid – condensation

Liquid to Solid- freezing

The average kinetic energy of the particles of a sample of matter is directly related to its temperature. The volume of the sample is irrelevant.

Use the concentration formula given on Reference Table T. Molarity is defined as the number of moles of solute per liter of solution.

Real gases behave least ideally when they are subject to intermolecular forces and the volume of the gas is no longer negligible. These conditions occur when the gas particles are made to move more slowly and allowed to approach each other more closely, that is under conditions of low temperature and high pressure.

ABC RULE

Ideal to Real ( I comes before R)

Pressure Increase or High ( P comes before T)

Temperature Decrease or Low ( T comes after P)

Only mixtures can be separated into different substances by physical means.

Avogadro’s Hypothesis states that at a given temperature and pressure (STP in this question), equal volumes of gases will contain the same number of particles.

An ideal gas consists of particles that have negligible volumes. These particles also have mass; move in random, constant, straight-line motion; undergo perfect elastic collisions (energy is not lost from the system just transferred from one particle to the other); and have no attraction for each other, except during collisions.

A chemical reaction occurs when the reacting particles are able to undergo effective collisions. An effective collision is one in which the colliding particles have sufficient kinetic energies and are oriented properly toward one another.

When a system reaches equilibrium, the rates of the forward and reverse reactions become equal.

30 Students are in your Chemistry Class.

CASE 1.

15 students are outside the room and 15 students are inside.  When one enters one leaves, When two enters two leaves. This case is at equilibrium because there is always a constant number of students in the room 15, and there is always a constant number of students outside the room, 15. Coincidentally the number of students in the room and outside the room is equal – the situation does NOT need to have equal number to be at equilibrium.

CASE 2.

20 Students are outside the room and 10 students are inside the room. When one student enters one leaves, when two enters two leaves. The system is at equilibrium because there is a constant number of students outside the room 20, and there is a constant number of students inside the room 10. The number of students outside the room is NOT equal to the number of students inside the room yet the system is AT equilibrium.

Organic compounds must contain at least one carbon atom. They may also contain chlorine, nitrogen, or oxygen atoms,  the only essential element common to these compounds is carbon.

http://www.lakelandschools.us/lh/lburris/pages/kinetics.htm

The difference between the potential energy of the reactants and the products is equal to the heat of the reaction (ΔH).

( PE of Products – PE of Reactants = Heat of reaction)

If the PE of the products is greater than the PE reactants the ΔH is positive. (endothermic)

If the PE of the products is less than the PE of the reactants the ΔH is negative. (exothermic)

See Reference Table P, Q, and R. the presence of a carbon-carbon triple bond places a hydrocarbon in the alkyne family with a suffix of -yne at the end of its name.

Electrolytic cells are electrochemical cells that use an external source of electrical energy in order to drive a nonspontaneous reduction-oxidation reaction.

An Arrhenius acid is defined as a substance that produce H⁺ ions as the only positive ion in an aqueous solution. See Reference Table K for a list of common Arrhenius acids, such as HCl.

One alternate acid-base theory is based on H⁺ transfer. An acid is defined as an H⁺ donor.

See Reference Table O. The two neutral particle on this table are gamma rays and neutrons. Gamma rays have no mass. [THE HULK]

Titration is the laboratory process that can be used to determine the concentration of an unknown solution (in this case NaOH(aq) by using a known volume of a solution whose concentration is known (such as HCl(aq).

Reference Table N. H-3 is the same as 3H.

Nuclear reactions such as fission and fusion release far more greater energy than ordinary chemical reactions.

Isotopes of the same element must have the same atomic number, i.e., protons.

Use the Periodic Table of elements. All Group 13 elements have 3 valance electrons. Lewis electron-dot diagrams display only the valance electrons of the atom.

Use the Periodic Table of Elements. Chlorine (Cl atomic number 17) has an oxidation number of -1. In the compound MCl, the oxidation state of M must be +1.

When dividing two measured quantities, the answer should contain the same number of significant figures as the quantity with the smaller number of significant figures. The mass is expressed to 5 significant figures and the volume to 2. The answer must contain 2 significant figures.

– If you are adding or subtracting report your answer to the least number of decimal places.

Use the Periodic Table of the Elements and Reference Table S. As one proceeds across Period 3 from Na to Ar, the properties of elements change from metal to metalloid to nonmetal to noble gas. Therefore, the metallic properties decrease. Table S reveals that the atomic radii of the eight successive elements all decrease from 190 pm to 88 pm.

The empirical formula of a compound is its molecular formula reduced to the simplest whole-number ratio possible.

Use the Periodic Table of Elements. When atom bond, they generally complete a valence shell that will contain either 2 or electrons. Since an atom of argon (Ar, atomic number 18) is a noble gas and already has 8 valance electrons, it will not bond with another atom.

Use Reference Table S. In a nonpolar bond, the electronegativity difference should be as close as possible to 0.  The electronegativity difference of the C-C bond is exactly 0.

“nonpolar covalent bond” – its is not about symmetry choice  with methane CH₄ is symmetrical and I would have selected this as my answer however the question asks which molecule has a nonpolar covalent ‘BOND’.

Use Reference Table H. At 50ºC,  ethanoic acid, has the lowest vapor pressure. (and propanone has the highest)

The diagram in this question indicates that substance G has a higher potential energy than substances A and G. This reaction is endothermic and has a positive ΔH. Use Reference Table I (as in India).

Use the combined gas law equation on Reference Table T.  At constant pressure the equation reduces to: V₁/T₁ = V₂/T₂

where the temperature is always measured in kelvins (K). If the Kelvin temperature doubles, the volume of the gas will double.

Reference Table F indicates that compounds containing the perchlorate  ion are always soluble in water

In the forward reaction, energy appears as a product, i.e., it is an exothermic reaction. If the temperature of the system is lowered, Le Chatelier’s principle predicts that the system will shift to the right in order to produce more heat energy. As a result, the concentration of both hydrogen and nitrogen will decrease and the concentration of ammonia will increase.

An unsaturated hydrocarbon contains only carbon and hydrogen with at least one double or triple bond between two adjacent carbon atoms.

In a reduction half-reaction, electrons are gained and the oxidation number of the reduced substance is lowered. The correct answer choice indicates that 2 electrons are gained and that the oxidation number of Fe is lowered from +2 to 0.

Use Reference Table J. Metals that are more active than Hydrogen lie above hydrogen on the table.

According to the ionic equation, Zn is oxidized to Zn²⁺ and is the anode; Cu²⁺ is reduced to Cu and is the cathode. The electrons lost by the Zn electrode pass thought the external circuit and enter the Cu electrode.

An electrolyte is a substance that conducts electricity dissolved in water. To test the conductivity of KCl, it must first be dissolved in water. Therefore KCl(aq) is needed.

the balanced neutralization reaction between HCl(aq) and Ca(OH)₂(aq) is shown below:
2HCl(aq) + Cu(OH)₂ (aq) → CaCl₂(aq) + 2H₂O(l)

See Reference Table-N. Carbon is a component of all living organisms. The radionuclide C-14 decays to stable C-12 and has a half-life of 5730 years. This combination is ideal for determining the age of once-living organisms, provided that they are not more than 20,000-25,000 years old.