Section A—Multiple choice (21 marks) 1 Hydrogen peroxide: A is water B has one more hydrogen atom than water C has one more oxygen atom than water D is none of the above. C 1 2 The atomic number of an element is equal to the number of: A electrons and neutrons B protons C neutrons D protons, neutrons and electrons. B 1 3 Which one of the following is not a property of non-metals? Non-metals are: A normally gases or liquids at room temperature B either poor electrical conductors…
The number of neutrons = mass number – atomic number. 9. Isotopes are atoms with equal numbers of protons, but differ in their neutron numbers. 10. Cations are positive (+) ions and form when a neutral atom loses electrons. They are smaller than their parent atom. 11. Anions are negative ions and form when a neutral atom gains electrons. They are larger than their parent atom. 12. Ernest Rutherford’s gold foil experiment showed that an atom is mostly empty space…
physical property is one that is displayed without any change in composition Chemical Property: Any characteristic that gives a sample of matter the ability/inability to undergo a change that alters its composition. Examples: Alkali metals react with water; Paper's ability to burn. Physical Change: Change in which the matter's physical appearance is altered, but composition remains unchanged. (Change in state of matter) Chemical Change: Change in which one or more kinds of matter are transformed to new…
Study Guide for Aqueous Systems and Solutions Test Chapter 15 1. Know unique properties of water and ice a. Liquid water: high surface tension (minimizing surface area) and low vapor pressure (therefore high boiling point) b. Ice: less dense than liquid water (due to open framework of water molecules arranged like a honeycomb) and floats (due to lower density) 2. Be able to identify solute and solvent in various types of solid, liquid and gaseous solutions a. solvent dissolves the solute…
acids is that acids are compounds that give off H+ ions when they react with another compound. Likewise, this definition says that bases are compounds that accept H+ ions from other compounds. The Arrhenius definition of acids says that they’re compounds that give off H+ ions in water and that bases are compounds that give off OH- ions in water. These definitions are the same. Basically, if you have something that can give off H+ in water it’s and acid. As a result, all acids have hydrogen…
hemistry C2 revision booklet Atoms, Molecules and Ions. AN ATOM is the smallest particle of an element. They cannot be split into smaller particles in chemical reactions. Iron is made of iron atoms (Fe). Sulphur is made of sulphur atoms (S) A MOLECULE is a small group of atoms joined together. The atoms may be the same (e.g. O2) or different (e.g. H2O). The chemical formula shows the number and type of atoms present. Non-metal…
and other gases (1%) The composition of air You need to know the proportions of the main gases in the atmosphere. The Earth's atmosphere has remained much the same for the past 200 million years. The pie chart shows the proportions of the main gases in the atmosphere. It is clear that the main gas is nitrogen. Oxygen - the gas that allows animals and plants to respire, and fuels to burn - is the next most abundant gas. These two gases are both elements and account for about 99% of the gases in the atmosphere…
names of Group IA, IIA, VIIA, and noble gases; actinides and lanthanides Describe the formation of ions from atoms Know common polyatomic ions Find the oxidation number (Roman numeral) of an element, either free or in a compound Write the name from the formula and write the formula from the name of these types of inorganics: binary ionic compounds, binary compounds composed of 2 nonmetals, ternary compounds, binary acids, and ternary acids Old AP test questions – Copyright College Board…
freshly cut surface is a shiny, silver colour, but this tarnishes quickly to a dull grey as the metal reacts with oxygen and water in the air. Pieces of such metals are stored in oil to prevent these reactions. Handling alkali metals Because the alkali metals are so reactive, care has to be taken when using them. They must not be touched because they will react with the water in sweat on the skin. Gloves may be used, and goggles should be worn. Physical properties of the alkali metals: Melting point…
the ions involved in the equilibrium: For example, suppose we added several drops of concentrated HCl solution (which contains the chloride ion at high concentration). According to Le Chatelier’s principle, the equilibrium will shift so as to consume some of the added chloride ion. This would result in a net decrease in the amount of NaCl that could dissolve. If we watched the saturated NaCl solution as the HCl was added, we should see some of the NaCl precipitate as a solid. Complex Ion Equilibria…
