Answer:So, one mole of water has a mass of 16 +1+1 = 18 grams. So, if one mole has a mass of 18 grams, 25 grams would have a mass of 25 grams/ 18 grams per mole or 1.39 moles
Answer:
2K + Br2 --> 2KBr is the answer
Camels lose less water through their urine and feces than many other mammals. Their kidneys concentrate water heavily, leading to salty urine. The intestines also reabsorb water from intestinal material as it is digested, so dry feces are produced.
The molecules of hydrogen gas that are formed is when 48.7 g of sodium are added to water is 6.375 x 10²³ molecules
<u><em>calculation</em></u>
2 Na +2H₂O → 2 NaOH +H₂
Step 1: find the moles of sodium (Na)
moles =mass÷ molar mass
from periodic table the molar mass of Na = 23 g/mol
moles= 48.7 g÷ 23 g/mol =2.117 moles
Step 2:use the mole ratio to determine the moles of H₂
from given equation Na:H₂ is 2:1
therefore the moles of H₂ = 2.117 moles x 1/2=1.059 moles
Step 3: find the molecules of H₂ using the Avogadro's law
According to Avogadro's law 1 mole = 6.02 x 10²³ molecules
1.059 moles = ? molecules
by cross multiplication
= [(1.059 moles x 6.02 x10²³ molecules) / 1 mole] =6.375 x 10²³ molecules
Answer:
d) A - 70% B - 30%
Explanation:
If x is the abundance of A, and 1−x is the abundance of B, then:
x (32.0) + (1−x) (33.0) = 32.3
32x + 33 − 33x = 32.3
33 − x = 32.3
x = 0.7
The abundance of A is 70%, and the abundance of B is 30%.
