Lecture 2 – Elements, Compounds, Measurements, and Scientific Notation

These flashcards cover key concepts related to elements, compounds, measurements, and scientific notation, as discussed in Lecture 2.

What are the two types of substances mentioned in the lecture?

Mixtures and pure substances.

How can you differentiate between a mixture and a pure substance?

A mixture can be homogeneous or heterogeneous, while a pure substance can be an element or compound.

What is a chemical formula?

A notation for a chemical compound using element symbols and subscripts to show how many atoms of each element are present.

What does a subscript indicate in a chemical formula?

The number of atoms of each element in a chemical compound.

In a chemical reaction, what are reactants?

Substances that undergo change during a chemical reaction, written on the left.

What are products in a chemical reaction?

Substances formed as a result of a chemical reaction, written on the right.

What is scientific notation?

A way of expressing numbers as a product of a number between 1 and 10, times 10 raised to a power.

What is the first step to express a number in scientific notation?

Move the decimal place until there is one non-zero digit in front of it.

What do the terms 'mass,' 'volume,' 'temperature,' and 'density' represent?

They are examples of physical quantities.

What is a 'unit' in measurement?

A defined quantity used as a standard of measurement.

What will the exponent be if the starting number is greater than one?

The exponent will be positive.