Chemistry - Periodic Table and Trends
If an atom of Carbon-14 has an atomic number of 6, how many neutrons does it possess?
8 neutrons (Mass number 14 minus atomic number 6)
What type of chemical bond forms between non-metal atoms via the sharing of valence electrons?
Covalent bond.
What type of chemical reaction occurs when a single complex reactant breaks down into two or more simpler products?
Decomposition.
According to the Arrhenius model, what specific ion is released into an aqueous solution by an acid?
Hydrogen ions
: Calculate the molar mass of water
18.0g/mol
Identify the Period 4 element located in Group 10 of the periodic table.
Nickel ($\text{Ni}$).
What is the systematic name for the compound N2O4
Dinitrogen tetroxide
Balance the following skeleton equation:
Al + O2 Producing Al2O3
What is the name of the binary acid represented by the formula HBr
Hydrobromic Acid
According to collision theory, what two criteria must reacting particles meet during a collision for a reaction to successfully occur?
They must have the correct spatial orientation and possess a minimum amount of energy (activation energy).
What happens to the atomic radius of elements as you move from left to right across a period, and why?
It decreases, because the increasing positive nuclear charge (more protons) pulls the electron shells closer to the nucleus.
What is the correct chemical formula for the compound Cobalt(III) sulfate?
Co3(SO4)3
Predict the products and write a balanced equation for the reaction between Hydrochloric acid and Sodium hydroxide.
sodium chloride and water.
How does the Brønsted-Lowry definition broaden our understanding of bases compared to the Arrhenius model?
It defines a base as a proton acceptor, which includes compounds that don't release hydroxide ions directly (like ammonia,
How many moles are contained in a 44 g sample of carbon dioxide?
1.0 mole.
Explain the trend in reactivity as you go down Group 1 (Alkali Metals), providing a structural reason
Reactivity increases down the group because valence electrons are farther from the nucleus, lowering ionization energy and making the electron easier to lose
Define the term "electrostatic force" in the context of how an ionic compound like NaCl stays bound together.
It is the strong physical attraction between oppositely charged ions (positive cations and negative anions) following electron transfer.
Complete and balance the complete combustion reaction for propane gas:
Propane is C3H8
carbond dioxide and wter.1, 5, 3, 4
If you look at a molecular simulation of two acids of equal concentration, how can you visually tell a weak acid apart from a strong acid?
The strong acid will be completely dissociated into individual ions, whereas the weak acid will show mostly intact, unbonded neutral molecules alongside a tiny amount of free ions
Use the concepts of bond-breaking and bond-making to explain why a chemical reaction might have a net negative change in enthalpy
More energy is released when making new bonds in the products than the energy absorbed to break bonds in the reactants, resulting in an exothermic process.
Which element has a higher electronegativity: Oxygen or Sulfur? Explain using shielding effects.
t has fewer electron shells (less shielding), allowing its nucleus to exert a stronger attractive force on shared bonding electrons.
Write out both the chemical formula for Ammonium phosphate and state the total number of atoms present in one formula unit of it.
(NH4)3(PO4. containing 20 atoms.
Predict whether a reaction will occur when solid copper (Cu is placed into a solution of Zinc nitrate, and explain your reasoning using single replacement rules.
No reaction occurs, because copper is less reactive than zinc and cannot displace it from a compound
Write out the chemical formula for Nitrous acid and state its conjugate base according to the Brønsted-Lowry model.
Formula: HNO2 Conjugate base: Nitrite ion NO2
Explain how adding a catalyst increases the rate of reaction without increasing the temperature or changing the kinetic energy of the particles.
A catalyst provides an alternative reaction pathway with a lower activation energy, meaning a higher percentage of existing collisions now have sufficient energy to react.