Elements, Compounds and Mixtures
What is matter made up of only one type of atom?
What is an element?
What is the positively charged particle located in the nucleus of an atom?
What is a proton?
he Periodic Table is arranged into rows and columns. What are the rows called?
What are periods?
When you crush a can, you are causing this type of change.
What is a physical change?
This law states that mass is neither created nor destroyed during a chemical reaction.
What is the Law of Conservation of Mass?
A substance formed when two or more elements are chemically bonded together in a fixed ratio.
What is a compound?
What are the three subatomic particles that make up an atom?
What are protons, neutrons, and electrons.
Elements in the same column, or group, have similar properties. What is a key property they share?
What is the same number of valence electrons?
What type of change occurs when a new substance is formed?
What is a chemical change?
The starting substances in a chemical reaction are called this.
What are reactants?
A glass of salt water is an example of this type of matter.
What is a mixture?
Which subatomic particle has no charge?
What is a neutron?
As you move from left to right across a period, the atomic number generally increases by how much?
What is by one?
List two indicators that a chemical reaction has occurred.
What are changes in energy (heat/light), color change, formation of a gas (bubbles), or formation of a precipitate?
In the chemical equation 2H2+O2→2H2O, what are the products?
What is 2H2O?
What is the key difference in how atoms are arranged in a compound versus a mixture?
What is that a compound has atoms chemically bonded together, while a mixture has atoms or molecules that are physically combined but not chemically bonded?
An electron is much smaller than a proton. How do their charges compare?
What is they have opposite but equal charges? The electron is negative, and the proton is positive
The modern Periodic Table is arranged by increasing atomic number. What was the property used to organize the early periodic table?
What is atomic mass?
Melting ice is a physical change, but burning wood is a chemical change. Explain why.
What is because melting ice is a change of state (solid to liquid), but the substance is still water, while burning wood turns wood into new substances like ash and carbon dioxide?
The number placed in front of a chemical formula to balance a chemical equation is called what?
What is a coefficient?
Classify the following as an element, compound, or mixture: H₂O, NaCl, O₂, and sweetened iced tea.
What is H₂O and NaCl are compounds, O₂ is an element, and sweetened iced tea is a mixture?
Use a model to illustrate the structure of a helium atom.
What is a model showing two protons and two neutrons in a central nucleus, with two electrons orbiting the nucleus?
Which family of elements is highly unreactive and found in Group 18?
What are the noble gases?
Classify each as a physical or chemical change: a) bending a wire; b) baking a cake; c) dissolving sugar in water.
What is a) physical, b) chemical, and c) physical?
Explain how a balanced chemical equation supports the Law of Conservation of Mass.
What is that a balanced equation shows the same number of each type of atom on both the reactant side and the product side, demonstrating that atoms are only rearranged and no mass is lost or gained?