Answer:
8.8g of Al are necessaries
Explanation:
Based on the reaction, 2 moles of Al are required to produce 3 moles of hydrogen gas.
To solve this question we must find the moles of H2 in 11L at STP using PV = nRT. With these moles we can find the moles of Al required and its mass as follows:
<em>Moles H2:</em>
PV = nRT; PV/RT = n
<em>Where P is pressure = 1atm at STP; V is volume = 11L; R is gas constant = 0.082atmL/molK and T is absolute temperature = 273.15K at STP</em>
Replacing:
1atm*11L/0.082atmL/molK*273.15K = n
n = 0.491 moles of H2 must be produced
<em />
<em>Moles Al:</em>
0.491 moles of H2 * (2mol Al / 3mol H2) = 0.327moles of Al are required
<em />
<em>Mass Al -Molar mass: 26.98g/mol-:</em>
0.327moles of Al * (26.98g / mol) = 8.8g of Al are necessaries
Answer: When objects fall to the ground, gravity causes them to accelerate. Acceleration is a change in velocity, and velocity, in turn, is a measure of the speed and direction of motion. Gravity causes an object to fall toward the ground at a faster and faster velocity the longer the object falls.
Explanation:
Answer:
HF + LiOH = LiF + H2O.
Explanation:
Hydofluoric acid is a weak acid the solution would be slightly basic due to the following equilibrium (condition in the course of a reversible chemical reaction in which no net change in the amounts of reactants and products occurs.)
Hope that helps. x
Explanation:
Given parameters:
Mass of Br-79 = 78.918 amu
Abundance = 50.69%
Unknown:
Mass of Br - 81 = ?
Solution:
Relative Atomic mass of Br = 80
The proportion by which each fraction of an isotope occurs in nature is called the geonormal abundance.
RAM = Ma Ba + McBc
The formula above is used to find the average mass of the given isotopes.
Since we know the percentage abundance of Br-79, that of Br-81 = 100-50.69= 49.31%
RAM = Ma Ba + McBc
RAM = relative atomic mass
Ma Ba = mass and abundance of Br-79
McBc = mass and abundance of Br-81
80 = (78.918 x 
) + ( 
x C)
80 = 40 + 0.49C
0.49C = 40
C = 
= 81.63amu
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Isotopes brainly.com/question/10862182
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Answer:
D
Explanation:
tropical areas receives the most solar radiation because the sun's rays are nearly perpendicular to the earths surface
