1. Hydrogen has 1 electron.
Fireworks changes chemical energy into light energy
Answer: C2H2
Explanation: Because each of the lines represent one bond, and because there are three lines (bonds) between the carbons, it means that they are bonded by three bonds, also known as a triple bond.
Answer:

Explanation:
1. Number of electrons

2. Number of protons

3. Identify the ion
An atom with 26 protons is iron, Fe.
A neutral atom of iron would have 26 electrons.
The ion has only 24 electrons, so it has lost two. The ion must have a charge of +2.

Explanation:
Hardness test — Scratch the rock with a fingernail, a copper penny, a glass plate or nail, and a ceramic plate. Check your Guide to assign it a rating on the Mohs Scale of Hardness.
Color streak test — Test for the “color streak” of the minerals by rubbing the rock across the ceramic plate in the Mineral Test Kit, or across smooth
cement. Look up which colors indicate which minerals are present.
Magnetism test — Hold the magnet in the Mineral Test Kit near your rock. If there is a magnetic pull, it has a metal mineral in it.
Acidity test — Put vinegar in the bottle included in the Mineral Test Kit. Squeeze out a few drops on the rock. If it fizzes, it contains carbonate.
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