Answer:
C
Explanation:
Wind is an agent of weathering so it would be C or D.
But D is incorrect because it doesn’t need to interact with anything
Complete question :
A jeweler has five rings, each weighing 18 g, made of an alloy of 10% silver and 90% gold. She decides to melt down the rings and add enough silver to reduce the gold content to 75%. How much silver should she add?
Answer:
Kindly check explanation
Explanation:
Given the following :
Weight of each alloy = 18g
Initial % of Silver = 10% = 0.1
Initial % of Gold = 90% = 0.9
New % of gold = 75% = 0.75
Hence, new % of silver will be (1 - 0.75) = 0.25
Let the amount of silver to be added = s
Hence,
Initial gold content = final gold content + added silver
18 * 0.9 = 0.75(18 + s)
16.2 = 13.5 + 0.75s
16. 2 = 13.5 + 0.75s
16.2 - 13.5 = 0.75s
2.7 = 0.75s
s = 2.7 / 0.75
s = 3.6
S = 3.6
Hence the amount of silver needed per ring in other to reduce the gold content = 3.6g
Total for the 5 rings = (3.6 * 5) = 18g
The answer is d because the pupa os the stage when the insects change to adults
Answer:
5. The valence electrons of both fluorine and carbon are found at about the same distance from their respective nuclei but the greater positive charge of the fluorine nucleus attracts its valence electrons more strongly.
Explanation:
Both fluorine and carbon are located in the second period of the periodic table, it means that they have 2 shells, so the valence electrons are found at about the same distance from their respective nuclei.
But fluorine has a higher atomic number, 9, than the carbon, 6. The atomic number represents how many protons there are in the nucleus, then there are more protons (positive charge) at the fluorine nucleus, and because of that, the attraction force between the nucleus and the valence electron is stronger in fluorine.
If the force is stronger, it will be necessary more energy to break the bond, so it will be harder to remove an electron from fluorine than from carbon.
