Answer:
A:UNDERSTANDING CONCEPTS PART A 13) Which of the following is an example of periodicity? A) eating breakfast
The symbol for the hydroxide ion is OH-
Answer:
not sure about it .I also need an answer
Answer:
In science, sound is defined as the transfer of energy from a vibrating object in waves that travel through matter. Most people commonly use the term sound to mean what they hear when sound waves enter their ears. The tree above generated sound waves when it fell to the ground, so it made sound according to the scientific definition
Explanation:
sound waves
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g