Answer:
Explanation:
Groundwater is stored in the open spaces within rocks and within unconsolidated sediments. Rocks and sediments near the surface are under less pressure than those at significant depth and therefore tend to have more open space. For this reason, and because it’s expensive to drill deep wells, most of the groundwater that is accessed by individual users is within the first 100 m of the surface. Some municipal, agricultural, and industrial groundwater users get their water from greater depth, but deeper groundwater tends to be of lower quality than shallow groundwater, so there is a limit as to how deep we can go.
Answer: we learned this not to long ago i think its a,c
Explanation:
<span>The student is incorrect because helium has 2 valence electrons and it's in group 18 because the first energy level is full. Although helium is placed in Group 18 which generally has 8 valence electrons, it does not have 8 valence electrons as the student suggested. It was grouped together with the noble gases because it exhibits similar properties with them. </span>
Gas x would be carbon dioxide.
note/ acid + carbonate —> salt + water + carbon dioxide
the white precipitate would be calcium carbonate. CaCo₃
note/ this is a common eqn u need to remember.
X - CO₂ (carbón dioxide)
Y - CaCo₃ (calcium carbonate)
sodium carbonate is a basic salt