Chem Flashcards
What are the trends in melting point and boiling point?
Trends in melting point and boiling point vary across periods and down groups.
What are the physical properties of metals?
The physical properties of metals include electrical conductivity, thermal conductivity, malleability, and ductility.
What are the chemical properties of Period 2 and 3 elements with oxygen?
Understand the products and reactivity of all Period 2 and 3 elements with oxygen.
How do metals react with oxygen, water, and acids?
Metals react with oxygen, water, dilute hydrochloric acid, and dilute sulfuric acid.
What is oxidation?
Oxidation is the loss of electrons or the gain of oxygen.
What are displacement reactions?
Displacement reactions involve redox reactions where oxidation and reduction occur simultaneously.
How does bonding change across a period?
Bonding changes from metallic to covalent and structure changes from giant to simple molecular.
How does bonding change down a group?
Bonding in elements becomes more metallic in character down a group.
What explains changes of state at melting and boiling points?
Changes of state can be explained in terms of particle movement and energy.
What are the trends in melting and boiling points?
Trends in melting and boiling points can be explained in terms of bonding and structure.
How do you predict the formulae of simple oxides of Period 2 and 3 elements?
You can predict the formulae based on their reactivity with oxygen.
What are the properties of simple oxides of Period 2 and 3 elements?
Properties include melting and boiling points, solubility in water, and acid-base nature.
What is the trend in reactivity of metals?
Reactivity of metals increases down groups 1 and 2 and decreases across periods 2 and 3.
What factors affect the trend in reactivity of metals?
Factors include nuclear attraction for outer shell electrons, nuclear charge, shielding, and atomic radius.
How do you determine the oxidation number of an element?
Determine the oxidation number of an element on its own, in a compound, or in an ion.
How do you identify an element that is oxidised?
Identify it by showing an increase in oxidation number.
What are expected observations in displacement reactions?
Expected observations include color change and heat given out.
What are the uses of oxides of Period 2 and 3 elements?
Uses are based on their properties, bonding, and structure.
What are the uses of hydroxides, chlorides, and sulfates of group 1 and 2 elements?
Uses are based on their properties, bonding, and structure.
What is covalent bonding?
Strong electrostatic attraction between two nuclei and the shared pairs of electrons between them
Involves sharing a pair of electrons between two atoms.
What do dot and cross diagrams represent?
Electrons in simple covalent molecules, including those with multiple bonds and dative covalent bonds
Useful for visualizing electron sharing in covalent bonds.
How are bond lengths and bond strengths related in covalent bonds?
As the number of shared pairs of electrons increases, bond length decreases and bond strength increases.
What is the tetrahedral basis of organic chemistry?
Carbon has four outer shell electrons and can form up to 4 single bonds, resulting in tetrahedral shapes.
Define metallic bonding.
Electrostatic attraction between positive metal ions and delocalised electrons.
What are delocalised electrons?
Electrons that are free to move and are formed by the loss of outer shell electrons from metal atoms.
List the three main types of intermolecular forces.
- Van der Waals
- Dipole-dipole
- Hydrogen bonding
What is a dative covalent (coordinate) bond?
A covalent bond in which the pair of electrons being shared is donated by one atom.
What is the bond angle associated with 4 bonding electron pairs around a central carbon atom?
109.5°
True or False: Hydrogen bonding is stronger than covalent bonding.
False
What is the relationship between electronegativity and permanent dipoles?
Permanent dipoles arise from a difference in electronegativity between the two atoms bonded.
What is the relative atomic mass?
The mean mass of the isotopes of an element compared to the mass of a carbon-12 atom.
Fill in the blank: A giant covalent structure is a ______ of many atoms bonded covalently.
[lattice]
How do intermolecular forces affect the physical properties of substances?
They influence melting point, boiling point, and density.
What does the term ‘van der Waals forces’ refer to?
Intermolecular forces that involve dipole attraction between molecules.
What type of bond occurs in polar molecules like H2O, NH3, and HF?
Hydrogen bonding.
What are the state symbols used in balanced equations?
- (s) - solid
- (l) - liquid
- (g) - gas
- (aq) - aqueous
How can you predict if a compound has covalent bonding?
From its name or formula.
Explain the effect of molecular size and shape on temporary dipole-induced dipole attractions.
The size and strength of the temporary dipole-induced dipole attraction depends upon the number of electrons and the molecular shape.
What is the formula for hydroxide?
OH⁻
How are ionic compounds’ formulae determined?
From the charges on their ions.
True or False: Simple covalent molecules are held together by strong intermolecular forces.
False
What is the primary reason for the strength of hydrogen bonding?
It occurs in polar molecules which have N-H, O-H, or H-F bonds.
What is the definition of atomic number?
The number of protons in the nucleus of an atom.
How can you determine the number of protons or electrons in an atom or ion?
From the atomic number.
What does relative molecular mass refer to?
The sum of the relative atomic masses of all the atoms present in a compound.
How many particles are in 1 mole of any substance?
6.02 x 10^23 (Avogadro constant).
What is the molar mass of a substance?
The mass in grams of 1 mole of the substance.
What is molarity?
The number of moles of a substance dissolved in 1 dm³ of solution.
What are the quantities used in chemical reactions?
Mass, volume of solution, concentration, reacting quantities, percentage yields.
What is the formula to calculate the percentage yield of a product?
Percentage yield = (actual yield / theoretical yield) x 100.
What is the arrangement of elements in the periodic table based on?
Increasing atomic number.
What do elements in the same period have in common?
The same number of occupied shells in their atoms.
What defines the groups in the periodic table?
Elements in the same group have the same number of electrons in their outermost shell.
What is first ionisation energy?
The energy required to remove one mole of electrons from one mole of atoms in their gaseous state.
Why is the first ionisation energy considered an endothermic process?
Energy is absorbed to remove an electron.
How does ionisation energy trend across a period?
It generally increases.
How does ionisation energy trend down a group?
It decreases.
What does electron affinity measure?
The energy released when 1 mole of gaseous atoms gains 1 mole of electrons.
What is the trend in atomic radius across a period?
It generally decreases.
What is the trend in ionic radius down a group?
It generally increases.
What is electronegativity?
A measure of the tendency of an atom to attract a bonding pair of electrons in a covalent bond.
Fill in the blank: The number of moles is related to the number of particles through the _______.
Avogadro constant.
True or False: All elements in the same group exhibit similar chemical behavior.
True.
What is the significance of the highest subshell occupied by electrons?
It determines the block of the periodic table an element is found in.
What does the electronic arrangement of an element determine?
The chemical properties of the element.
How is the electronic configuration of elements represented?
Using s, p, d subshell notation.
What type of bonding is present in elements?
The type of bonding changes from metallic to covalent across a period.
What are the trends in melting point and boiling point?
Trends in melting point and boiling point vary across periods and down groups.
What are the physical properties of metals?
The physical properties of metals include electrical conductivity, thermal conductivity, malleability, and ductility.
What are the chemical properties of Period 2 and 3 elements with oxygen?
Understand the products and reactivity of all Period 2 and 3 elements with oxygen.
How do metals react with oxygen, water, and acids?
Metals react with oxygen, water, dilute hydrochloric acid, and dilute sulfuric acid.
What is the position of metals in the reactivity series?
The position of metals in the reactivity series relates to their position in the periodic table.
What is oxidation?
Oxidation is the loss of electrons or the gain of oxygen.
What is reduction?
Reduction is the gain of electrons or the loss of oxygen.
What are variable oxidation states?
Transition metal ions can have different oxidation states.
What are displacement reactions?
Displacement reactions involve redox reactions where oxidation and reduction occur simultaneously.
How does bonding change across a period?
Bonding changes from metallic to covalent and structure changes from giant to simple molecular.
How does bonding change down a group?
Bonding in elements becomes more metallic in character down a group.
What explains changes of state at melting and boiling points?
Changes of state can be explained in terms of particle movement and energy.
What are the trends in melting and boiling points?
Trends in melting and boiling points can be explained in terms of bonding and structure.
How do you predict the formulae of simple oxides of Period 2 and 3 elements?
You can predict the formulae based on their reactivity with oxygen.
What are the properties of simple oxides of Period 2 and 3 elements?
Properties include melting and boiling points, solubility in water, and acid-base nature.
What is the trend in reactivity of metals?
Reactivity of metals increases down groups 1 and 2 and decreases across periods 2 and 3.
What factors affect the trend in reactivity of metals?
Factors include nuclear attraction for outer shell electrons, nuclear charge, shielding, and atomic radius.
How do you determine the oxidation number of an element?
Determine the oxidation number of an element on its own, in a compound, or in an ion.
How do you identify an element that is oxidised?
Identify it by showing an increase in oxidation number.
What are expected observations in displacement reactions?
Expected observations include color change and heat given out.
What are the uses of oxides of Period 2 and 3 elements?
Uses are based on their properties, bonding, and structure.
What are the uses of hydroxides, chlorides, and sulfates of group 1 and 2 elements?
Uses are based on their properties, bonding, and structure.
