Answer:
heavier gases - sank to the surface
lighter gases - escaped into space
oxygen - produced through photosynthesis
carbon dioxide - released by volcanoes
Explanation:
Since the formation of the atmosphere on Earth, there has been constant changes in it, gradually leading to the atmosphere that we have nowadays. In the distant past, the atmosphere was much different, and it took lot of time for it to become what it is. The volcanoes with their activity contributed to constant release of carbon dioxide, resulting in the greenhouse effect. The organisms that are able to perform photosynthesis started to release lot of oxygen into the atmosphere, thus setting up better living conditions. The gravity of our planet contributed to the vertical distribution of the gasses, with the heavier being lower, and the lighter ones being further up or released into space.
Answer:
On the picture are all principles cited on wikipedia.
Explanation:
So the answer is
1. Environment must be exploited to improve living standards
2. Flourishing human and nonhuman life depends on diversity of life forms
Answer:
Explanation:
General reaction of acid in water is as follows:
HCl + H2O = H3O+ + Cl-
Thus Acids increase the concentration of hydronium ions in solution by donating hydrogen ions to water molecules is true
Answer:
Explanation:
H3PO4(aq) + 3NaOH(aq) → Na3PO4(aq) + 3H2O(l)
mole of NaOH = 23.6 * 10 ⁻³L * 0.2M
= 0.00472mole
let x be the no of mole of H3PO4 required of 0.00472mole of NaOH
3 mole of NaOH required ------- 1 mole of H3PO4
0.00472mole of NaOH ----------x
cross multiply
3x = 0.0472
x = 0.00157mole
[H3PO4] = mole of H3PO4 / Vol. of H3PO4
= 0.00157mole / (10*10⁻³l)
= 0.157M
<h3>The concentration of unknown phosphoric acid is 0.157M</h3>
The question is incomplete, the complete question is;
Which of the following is most likely a heavier stable nucleus? (select all that apply) Select all that apply: A nucleus with a neutron:proton ratio of 1.05 A nucleus with a A nucleus with a neutron:proton ratio of 1.49 The nucleus of Sb-123 A nucleus with a mass of 187 and an atomic number of 75
Answer:
A nucleus with a A nucleus with a neutron:proton ratio of 1.49
A nucleus with a mass of 187 and an atomic number of 75
Explanation:
The stability of a nucleus depends on the number of neutrons and protons present in the nucleus. For many low atomic number elements, the number of protons and number of neutrons are equal. This implies that the neutron/proton ratio = 1
Elements with higher atomic number tend to be more stable if they have a slight excess of neutrons as this reduces the repulsion between protons.
Generally, the belt of stability for chemical elements lie between and N/P ratio of 1 to an N/P ratio of 1.5.
Two options selected have an N/P ratio of 1.49 hence they are heavy stable elements.
