Measurement
These digits in a measurement are known with certainty, plus one estimated digit.
What are significant figures?
This substance is made up of only one type of atom.
What is an element?
The subatomic particle with a positive charge found in the nucleus.
The spontaneous emission of particles or energy from an unstable nucleus is called this.
What is radioactive decay?
Write 0.00045 in scientific notation.
What is 4.5 x 10-4?
This system of measurement is used by scientists worldwide for consistency.
What is the SI system?
A combination of two or more substances that are physically together but not chemically combined is called this.
What is a mixture?
This scientist developed the first atomic theory stating that atoms are indivisible and cannot be destroyed in a chemical reaction.
Who is John Dalton?
In this type of radiation, a helium nucleus is released.
What is alpha radiation?
Covert 250 cm to meters.
What is 2.5 meters?
A measurement close to the true value is said to be this.
What is accurate?
The ability of a substance to burn in the presence of oxygen is an example of this.
What is a chemical property?
This number identifies the element and tells you how many protons are in the atom.
What is the atomic number?
The time it takes for half of a radioactive sample to decay is known as this.
What is half-life?
The charge of a magnesium atom with 12 protons and 10 electrons is this.
What is +2?
When adding or subtracting measured values, your answer should be rounded to this place value.
What is the least number of decimal places?
What is a physical change?
This part of the atom contains nearly all of its mass but occupies very little of its volume.
What is the nucleus?
The process in which one element changes into another due to a change in its nucleus.
What is transmutation?
A 40 g radioactive sample with a half life of 10 minutes has this much left after 30 minutes.
What is 5 grams?
When multiplying numbers in scientific notation, you multiply the coefficients and do this to the exponents.
What is add them?
In this type of mixture, the different parts can be seen and easily separated.
What is a heterogeneous mixture?
This number is used to define an isotope.
What is mass number?
When a nucleus emits a beta particle, this happens to its atomic number.
What is it increases by one?
The atomic mass of calcium with its two isotopes (Ca-40, 60% and Ca-42, 40%) is this.
What is 40.8?