Chemistry concepts, explained
- What does Le Chatelier's principle predict?
Le Chatelier's principle predicts how a chemical system at equilibrium will shift its reaction rates to counteract a change in conditions.
- What is the difference between an acid and a base?
Acids are substances that donate protons (hydrogen ions) in a reaction, while bases are substances that accept those protons.
- What is activation energy?
Activation energy is the minimum amount of energy required to start a chemical reaction, acting like a barrier that reactants must overcome.
- How do you identify a redox reaction?
Learn how to identify a redox reaction by checking if oxidation states change, meaning electrons are transferred between atoms.
- How do you calculate pH?
Learn how to calculate pH from hydrogen ion concentration using the logarithmic formula, with step-by-step examples and common mistakes to avoid.
- How Do You Use the Ideal Gas Law?
Learn how to use the ideal gas law (PV = nRT) to find the pressure, volume, temperature, or amount of a gas, including step-by-step examples and tips.
- What is molarity and how do you make a solution?
Molarity measures the concentration of a solution in moles of solute per liter of solution. Learn the formula and how to prepare solutions accurately.
- What is a buffer and how does it work?
A buffer is a chemical solution that resists changes in pH when small amounts of strong acid or base are added, typically made of a weak acid and its salt.
- What makes a molecule polar?
A molecule is polar if it contains polar covalent bonds and has an asymmetrical shape, leading to an uneven distribution of electrical charge.
- How do you draw a Lewis structure?
Learn how to draw Lewis structures step-by-step, from counting valence electrons to placing bonds and lone pairs to satisfy the octet rule.
- How does VSEPR predict molecular shape?
VSEPR theory predicts molecular shape by assuming that electron pairs around a central atom repel each other and spread out as far apart as possible.
- What is the difference between ionic and covalent bonds?
Ionic bonds form when atoms transfer electrons to one another, while covalent bonds form when atoms share electrons to achieve a stable outer shell.
- How do you write an electron configuration?
Learn how to write an electron configuration by following the rules for filling atomic orbitals with electrons.
- What is the difference between an ion and an isotope?
An ion has a different number of electrons and carries a charge, while an isotope has a different number of neutrons and a different mass.
- What are periodic trends and why do they happen?
Periodic trends are predictable patterns in element properties across the periodic table, driven by atomic structure and effective nuclear charge.
- How do you find the limiting reactant?
Learn how to identify the limiting reactant in a chemical reaction by converting masses to moles and comparing them using the balanced equation.
- What is percent yield and how do you calculate it?
Percent yield compares the actual amount of product made in a reaction to the maximum possible amount, helping measure a reaction's efficiency.
- How do you balance a chemical equation?
Learn how to balance chemical equations using coefficients to satisfy the law of conservation of mass, with step-by-step examples and helpful tips.
- What is a mole and why do chemists use it?
A mole is a fundamental chemical unit used to count atoms and molecules by weighing them, making laboratory chemistry practical and possible.