Answer:
• All groups (columns) have the same number of valence electrons
Explanation:
Every group or column have the same number of valence electrons as a suprise. Every column is aligned in this way.
The correct answer is D.
Echo refers to the sound that is heard when a sound wave is reflected back from a surface. An echo sound is made when a sound wave traveled through the air, hit a hard surface and get reflected back. Generally, hard surfaces reflect sound wave while soft surfaces absorb sound waves. Reflected sound waves are used in application of some devices that are used in range and direction finding.
OD. A swing moving back and forth
Kinetic energy refers to the energy an object has while it is in motion. The swing is the only moving option.
Answer:
Luiquid
Explanation:
The atoms in a liquid state of matter have a definite volume, eventhough they acquire the shape of the container that contains them, the volume will always be the same, while in a solid the shape and volume will remain constant, on the other hand for a gas, the substance will fill the container where it is, having different volumes.
Answer:
Atomic number
Explanation:
Atomic number is the number of protons, and therefore also the total positive charge, in the atomic nucleus. The Rutherford–Bohr model of the hydrogen atom (Z = 1) or a hydrogen-like ion (Z > 1).