Answer:
so the third one
Explanation:
During the day, the sun heats up mountain air rapidly while the valley remains relatively cooler. Convection causes it to rise, causing a valley breeze. At night, the process is reversed. During the night the slopes get cooled and the dense air descends into the valley as the mountain wind.
The equilibrium expression shows the ratio between
products and reactants. This expression is equal to the concentration of the
products raised to its coefficient divided by the concentration of the
reactants raised to its coefficient. The correct equilibrium expression for the
given reaction is:<span>
<span>H2CO3(aq) + H2O(l) = H3O+(aq) + HCO3-1(aq)
Kc = [HCO3-1] [H3O+] / [H2O] [H2CO3]</span></span>
Answer:
2.765amu is the contribution of the X-19 isotope to the weighted average
Explanation:
The average molar mass is defined as the sum of the molar mass of each isotope times its abundance. For the unknown element X that has 2 isotopes the weighted average is defined as:
X = Mass X-19 * Abundance X-19 + MassX-21 * Abundance X-21
The contribution of the X-19 isotope is its mass (19.00 amu) times its abundance (14.55% = 0.1455). That is:
19.00amu * 0.1455 =
2.765amu is the contribution of the X-19 isotope to the weighted average
Answer:
Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth's surface.
