name= calcium
atomic mass= 40.078 atomic mass unit
no of protons= 20
no of electrons=20
Answer:
theirs a $50 tax with the income hes making
Explanation:
Answer:
The discipline of Earth and space science is concerned with the study of the planets and stars is
A. Astronomy
Explanation:
A.Astronomy:
'Astron' means stars and 'nomos' means laws. So astronomy is the study of stars , planets and space
B.
biology
It is derived from Greek word : 'Bios' means life and 'logos' means study.
Biology is study of life, living organism ,structure of organisms,evolution
C.Geology
It is the earth science which includes the study of rocks and solid earth, what it is made of and how it has changed .
D. Oceanography
It is the study of physical and biological aspects of oceans
Answer is: concentratio of H₃O⁺ ions is 4.2·10⁻³ M.<span>
Chemical reaction: HCOOH(aq) + H</span>₂O(l) ⇄ HCOO⁻(aq) + H₃O⁺(aq).<span>
c(HCOOH) = 0,1 M.
[</span>H₃O⁺] = [HCOO⁻] = x.<span>
[HCOOH] = 0,1 M - x.
</span>Ka = [H₃O⁺] · [HCOO⁻] / [HCOOH].
0,00018 = x² / (0,1 M - x).<span>
Solve quadratic equation: x = </span>[H₃O⁺] = 0,0042 M.
