Chemistry mid term part 1

Which of the following is true about compounds?

• They can be physically separated into the component elements
• Their elements are never in fixed ratios or proportions
• They are substances.
• They have properties similar to those of their elements

Which step in the scientific process requires you to use your senses?

• Making a hypothesis.
• Designing an experiment.
• Making an observation.
• Stating a theory.

The smallest particle of an element that retains the properties of that element is...

• A proton
• A Neutron
• An Electron
• An Atom

Which of the following are NOT physical properties of matter?

• Size and Color
• Mass and Volume
• Texture and Hardness
• Ability to rust.

The inner electrons help _________outer valence electrons from the nucleus.

• attract
• spin
• shield
• excite

An element has an atomic number of 76. Number of protons and electrons in the neutral element are

• 152 protons and 76 electrons
• 76 protons and 0 electrons
• 38 protons and 38 electrons
• 76 protons and 76 electrons

Which state of matter takes the shape of its container?

• solid
• liquid
• gas
• plasma

Isotopes of the same element have different ____.

• numbers of electrons
• atomic numbers
• numbers of neutrons
• numbers of protons

Which of the following is a physical change?

• corrosion
• explosion
• rotting of food
• evaporation

How many valence electrons are in an atom of phosphorus?

• 3
• 4
• 5
• 6