Is it multiple choice or do you just answer
Answer:
I think you meant rock defination in science
Explanation:
A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition and the way in which it is formed. Rocks are usually grouped into three main groups: igneous rocks, metamorphic rocks and sedimentary rocks.
or
A rock is a solid made up of a bunch of different minerals. Rocks are generally not uniform or made up of exact structures that can be described by scientific formulas. Scientists generally classify rocks by how they were made or formed. There are three major types of rocks: Metamorphic, Igneous, and Sedimentary.
Answer:
6.25% of the original amount
Explanation:
half-life means that half is gone for every certain period of time. Because the half life is 1 month, only half of the 'radionulide' is left every month.
after 1 month= 50%
after 2 months= 25%
after 3 months= 12.5%
after 4 months= 6.25%
Ca(OH)₂: strong base
pOH = a . M
a = valence ( amount of OH⁻)
M = concentration
Ca(OH)₂ ⇒ Ca²⁺ + 2OH⁻ (2 valence)
so:
pOH = 2 x 0.005
pOH = 0.01
pH = 14 - 0.01 = 13.99
