Unit 1 Quiz Flashcards
What is science?
A highly logical, systemic, and organized approach to problem-solving. This approach is referred to as the scientific method.
Types of particles
protons, electrons and neutrons
Properties of protons
positive charge (1+), smaller than atom, mass of 1u, located in the nucleus
Properties of electrons
Negative charge (1-), smaller than atom, mass of 1/1837u, located in orbit
Properties of neutrons
neutral (0), smaller than atom, mass of 1u, located in nucleus.
Define pure substance.
A form of matter which is made up of only 1 kind of particle.
Examples of a pure substance?
Glucose, pure gold bar, salt, helium gas, distilled water.
Define element.
A pure substance which cannot be further broken down by ordinary chemical means. Elements are made up of identical particles called atoms.
Examples of elements?
Hydrogen, oxygen, gold, silver.
What’s a chemical formula and what does it consist of?
A chemical formula is used to describe the composition of chemical make-up of a compound. A formula consists of 1 or more symbols.
Describe a Bohr-Rutherford atomic model.
- The atom consists of mostly empty space.
- Most of the mass of the atom is located in a central region called the nucleus.
- The nucleus consists of positively charged particles called protons as well as neutral particles called neutrons.
- Tiny negatively charged particles called electrons travel around the nucleus in well-defined paths called orbits.
What is the atomic number?
Corresponds to the number of protons or electrons present in a single atom.
What is the mass number?
Corresponds to the total number of particles present in the nucleus of a single atom (i.e. protons + neutrons).
What is a neutral atom?
An atom which contains the same number of protons and electrons.
How to calculate the number of neutrons:
Mass # - atomic #
Define matter.
Anything that has mass takes up space.
List the parts of the particle theory of matter.
- All matter is made up of tiny particles.
- All particles of a pure substance are identical.
- The space between particles in large compared to sizes of the particles themselves.
- Particles of matter are always moving.
- There are forces of attraction that exist between the particles of matter.
What is chemistry?
Chemistry is a science which studies substances, their properties, structure, composition, and transformations.
Define a compound.
A pure substance which is made up of 2 or more different types of elements. They consist of identical particles called molecules.
Identify the 6 steps associated with the scientific method.
- Identify the problem (purpose).
- Propose a solution to the problem (hypothesis).
- Test the proposed solution through experimentation (method).
- Gather data using the senses (observations).
- Analyse the data.
- Formulate conclusions (discussion).
What are cations?
Positively charged particles that are created when atoms lose electrons.
What are anions?
Negatively charged particles that are created when atoms gain electrons.
What are molecules?
Larger particles that are created when atoms join together.
