| A | B |
|---|
| NO and NO2 are examples of a compound pair that illustrate what law in chemistry? | Law of Multiple Proportions |
| True or False? The Rutherford experiment proved the Thomson "Plum-Pudding" model of the atom to be essentially correct. | False |
| True or False? The Rutherford experiment was useful in determining the nuclear charge on the atom. | True |
| True or False? Millikan's Oil-Drop experiment showed that the charge on any particle was a simple MULTIPLE of the charge on the electron. | True |
| The electric discharge tube (aka cathode-Ray tube) proved that electrons do have a negative charge. | True |
| According to TODAY's Modern Atomic Theory, is the following TRUE or FALSE? Elements are made up of tiny particles called atoms. | True |
| According to TODAY's Modern Atomic Theory, is the following TRUE or FALSE? Atoms are not created nor destroyed in a chemical reaction, but rather simply rearranged. | True |
| According to TODAY's Modern Atomic Theory, is the following TRUE or FALSE? All atoms of a given element are identical. | False...Isotopes of an element each have EXACT same number of Protons and Electrons, but do differ in the number of Neutrons held inside the nucleous. |
| According to TODAY's Modern Atomic Theory, is the following TRUE or FALSE? Atoms are indivisible in chemical reactions. | True.....Atoms are only rearranged |
| The first persons to attempt to explain why chemical changes occur were ? | The ancient GREEKS |
| The Greeks proposed that matter consisted of four(4) fundamental substances, what were these four substances? | F.E.W.A. or Fire,Earth,Water, and AIR |
| The first chemist to perform truly quantitative experiments was? | Robert Boyle |
| The scientist whom discovered the Law of Conservation of Mass is also called the Father of Modern chemistry.Who is that scientist? | Lavoisier |
| Between the following pairs of compounds, which could be used to illustrate the Law of Multiple Proportions? SO and SO2, CO and CaCO3, H2O and C12H22O11, H2SO4 and H2S, or KCl and KClO2.... | SO and SO2 could be used to illustrate the Law of Multiple Proportions. |
| I am the chemist that is credited for inventing a set of symbols for writing elements and a system for writing the formulas of compounds ( and for discovering the elements of selenium, silicon, and thorium). Who am I ? | BerZelius |
| In trace amounts, what element has been shown to help in protecting against heart disease and cancer? | selenium, but only in very minute amounts |
| I was the first scientist to show that atoms emit any negative particles, who am I? | J.J. Thomson |
| I am the scientist whose alpha-particle scattering experiment led me to conclude that the nucleus of an atom contains a dense center of positive charge. I am? | Ernest Rutherford |
| True or false? The electrons occupy a very large volume compared to the nucleus. | True |
| True or false? Almost all of the mass of the atom is concentrated in the very very small nucleus. | True |
| True or false?The protons and neutrons in the nucleus are very tightly packed. | True |
| True or false? The number of protons and neutrons is always the same in a neutral atom. | False...A neutral atom is simple any atom with same number of electrons as it has protons, the number of neutrons can vary without affecting the overall charge because although the mass of neutrons is close to that of a proton, it is NOT charged. |
| If the Thomson model of the atom had been correct (because it has been shown to NOT be correct), Rutherford would have observed which of the following? (a) alpha particles going through the foil with little of no deflection in his GOLD-FOIL experiments or (b) alpha-particles greatly deflected by the metal foil or (c) alpha-particles bouncing off the foil or (d) positive particles formed in the foil or (e) none of these statements are true. | Had Thomson been correct, Rutherford would of observed (A) alpha-particles going through the foil with little or no deflection. |
| Rutherford's Gold-Foil experiments was important because it showed what? | Rutherford's experiments showed that an atom is mostly EMPTY SPACE. |
| What is the name of the ion of S^2- | sulfide |
| What is the formula for ammonium chloride? | NH4Cl |
| What is the name of the substance with chemical formula of HC2H3O2 ? | acetic acid is HC2H3O2 or H4C2O2 |
| What is the chemical formula for barium oxide? | BaO |
| True or False? Carbon has atomic mass of 14 and atomic number of 6 | True, because carbon has 6 protons (atomin number) and atomic mass of 14 (because it has 6 protons and 8 neutrons) |
| What is the atomic number (number of protons) and atomic mass ( sum of protons and neutrons in the nucleus) of the element chlorine? | atomic number is 17( has 17 protons) and atomic mass is 37 ( has 20 neutrons) |
| True or false? Atomic Mass of phosphorus is 32 while its atomic number is 15? | True |
| Potassium (K) has 19 protons and 20 neutrons, what is the atomic mass and atomic number for the element potassium? | potassium , K, has 19 protons so its atomic number is 19.With 20 neutrons, the atoomic mass is 19+20=39 |
| The element rhenium (Re) does exist as two stable isotopes and 18 unstable isotopes. Rhenium-185 has in its nucleus how many protons and neutrons? | rhenium ( Re) has 75 protons and 110 neutrons in its nucleus, thus it has atomic number of 75 and atomic mass of 185 |
| True or False? The mass of an alpha particle is 7300 times that of the electron. | TRUE |
| True or False? An alpha particle has a 2+ charge. | True |
| True or False? Three (3) types of radioactive emission are gamma rays, beta rays, and alpha particles. | True |
| True or False? A gamma ray is HIGH-ENERGY LIGHT. | True |
| The only types of radioactivity known to scientist today are alpha particles, gamma rays, and beta rays. | False----there ARE other types of radioactivity known to scientist today |
| A calcium cation of +2 charge and an atomic mass of 40 has how many protons, neutrons and electrons? | Since its 2+ charged, it will have two LESS electrons than the number of protons it has. The atomic mass will be the sum of protons and neutrons, so 40-protons will tell how many neutrons there are. The number of protons of ALL calcium ions contain 20 protons inside the nucleus. SO, THERE are 20 PROTONS, 40-20= 20 NEUTRONS, and 20-2= 18 ELECTRONS. |
| What ion has 61 neutrons, 47 protons, and 46 electrons? | Any and all ions of the element silver ( Ag) have 47 protons. Since there are only 46 electrons, that means there is one more proton than electrons, so an OVERALL +1 charge will exist on this silver ion.The periodic table displays that the average silver isotope carries 61 neutrons, so the ion will be Ag+ , that is, SILVER ( as a cation, you call it the same name as you would the actual element, but show the charge in the superscript) |
| True or False? Ions are formed by adding electrons to a neutral atom. | True |
| True or False? Ions are formed by changing the number of protons in an atom's nucleus. | False....Changing number of Protons means you have actually got a completely new substance(element). Ions are only different from neutral atoms because ions possess a DIFFERENCE in the number of protons they hold in comparisons to the number of electrons it possesses. |
| True or False? Ions are formed by removing electrons from a neutral atom. | True...Altering number of neutrons will create an ion. Taking AWAY electrons forms CATIONS while adding electrons forms ANIONS. |
| True or False? An ion has either a positive or a negative overall net charge. | True, if the ion has MORE protons than electrons, it is a POSITIVE ION (called CATION). If the ion carries more electrons than it has protons, it is negatively charged and called an ANION. |
| By knowing the number of protons a neutral atom has, you should be able to determine the number of neutral atoms in the neutral atom. True or false? | False...Only if you KNOW the atomic mass and the atomic number could you determine the number of neutrons. |
| By knowing the number of protons a neutral atom has, you should be able to determine the number of electrons there are in a neutral atom.True or False? | True, because in neutral atoms, the number of electrons will be exactly the same as the number of protons |
| By knowing the number of protons a neutral atom has, you should be able to determine the name of an atom. | TRUE, sort of....If you know how many PROTONS there are in any atom, you can find that number on the periodic table of elements to determine what element that atom is an isotope of, hence you could name the neutral atom. |
| True or false? The number of neutrons in an atom is the same for all neutral atoms of that element? | FALSE...Different isotopes of the SAME ELEMENT will indeed have same number of Protons and ELECTRONS, but the differing isotopes will each have a DIFFERENT number of NEUTRONS ( differing Atomic Masses although the Atomic Numbers are same for all isotopes of an element) |
| The average mass of a carbon atom is 12.011 ( grams per mole).Assumming you were able to pick up only one carbon unit, the chances that you would randomly get one with a mass of exactly 12.011 is what? | NO CHANE ( 0% ) because each different isotope of any element will have a definitive whole number for its atomic mass, not 12.011...The 12.011 indicates only the AVERAGE of all the isotopes of that element. |
| The number of electrons in an atom is the same for all neutral atoms of that element, true or false? | TRUE--the number of electrons in any neutral atom is equal to the number of protons. |
| True or false? Adding or subtracting protons from an atom forms ions? | False---if the number of protons changes, the actual substance changes as well. Every element ( an its associated isotopes) all have the EXACT same number of PROTONS. Change of protons means a change of the actual element as well. |
| True or false? Adding or subtracting electrons from an atom forms an ion? | TRUE, in neutral atoms the number of protons equals the number of neutrons, if you add or subtract electrons you form either cations (taking away electrons) or Anions( adding electrons) |
| True or false? Adding or subtracting neutrons from an atom forms ions. | False...Only a change in number of electrons forms ions. changing Number of PROTONS alters the element itself, whereas change of number of neutrons only affects the Atomic MASS of an atom. |
| True or false? Uranium-238 has chemical properties exactly like that of uranium-235? | True, only difference is that U-238 has a greater Atomic Mass than U-235 |
| True or False? Uranium-238 has a mass that is slightly different than that of the isotope uranium-235? | True, they differ only in number of NEUTRONS each has--with U-238 having 3 more neutrons than would U-235. |
| True or false? Uranium-238 contains a different number of protons than that of the isotope uranium-235. | False, any and all atoms of uranium will each have EXACTLY the same number of protons as would anyother atom of uranium, NO EXCEPTIONS. |
| True or false? In nature, the uranium isotope U-238 is more plentiful than is U-235. | True |
| An isotope , X , of a particular element has an atomic number of 7 nd an atomic mass number of 15. Of what element is "X" an isotope of, how many protons, neutrons, and electrons would "X" possess? | Because "X" has 7 protons (atomic number) it must be an isotope of NITROGEN. With "X" having atomic mass of 15, there must be 8 neutrons . The isotope MUST have exact same number of electrons as it has protons, so "X" has 7 electrons also.. Therefore, "X" is a nitrogen isotope with 7 protons, 7 electrons and 8 neutrons |
| How many oxygen atoms are there in one formula unit of Ca3(PO4)2 ? ****NOTE, the numbers indicated are subscripts) | Ca3(PO4)2 has EIGHT(8) oxygen atoms in ONE FORMULA UNIT, because each formula unit of Ca3(PO4)2 has 2 molecules of PO4, and each PO4 has four(4) oxygen atoms. |
| True or False? The formula of water, H2O , suggests there is twice as much mass of hydrogen as oxygen in each molecule. | FALSE-----H2O only indicates that there are one moles of oxygen for every two moles of hydrogen. |
| True or False? The formula of water, H2O , suggests there are two hydrogen atoms and one oxygen atom per one water molecule. | TRUE |
| True or False? The formula of water, H2O , suggests there is twice as much mass of oxygen as hydrogen in each water molecule. | False, H2O only indicates that for every ONE molecule of water, there is twice as many hydrogen atoms as there are oxygen atoms. |
| True or False? The formula of water, H2O , suggests there are two oxygen atoms and one hydrogen atom per water molecule. | False, the opposite is true however. |
| True or false? Potassium, K , is an Alkali Metal | True, all first family (aka first group elements ) are Alkali Metals with the EXCEPTION of Hydrogen, which is a GAS. |
| Barium , Ba , is an Alkali earth Metal. | True, all elements in group (family) two are Alkali Earth Metals |
| True or false? Oxygen is a Halogen. | False, Oxygen is NOT in group(family) seventeen(17) therefore oxygen can NOT be a halogen. |
| Neon, Ne , is a noble gas. | True, all group (family) eighteen (18) elements are called NOBLE GASES. |
| True or False? Nickel, Ni , is a transitional metal. | True, any element from group 3-12 is considered to be a transitional metal, plus some additional elements that are to the LEFT of the SOLID STEPLIKE LINE on periodic table separating gases from transitional metals. |
