Answer:
Explanation:
molar volume at STP=22.4 L
given volume=50.0 L
number of moles=given volume/molar volume
number of moles=50.0/22.4
number of moles=2.2
1 mole of helium =6.023*10^23 atoms
2.2 moles of helium =6.023*10^23*2.2=1.3*10^24
therefore 50.0 L of helium contain 1.33*10^24 atoms
The sum of the masses of the reactants must equal the sum of the masses of the products; as required by
the Principle of Conservation of Mass.
Answer:
the deep sea floor. Known as the oceanic crust.
Explanation:
The deep seafloor (the oceanic crust) is made almost entirely of basaltic rocks, with peridotite underneath in the mantle. Basalts are also erupted above the Earth's great subduction zones, either in volcanic island arcs or along the edges of continents.
Hope this helps :)
Answer:
The pH value of the mixture will be 7.00
Explanation:
Mono and disodium hydrogen phosphate mixture act as a buffer to maintain pH value around 7. Henderson–Hasselbalch equation is used to determine the pH value of a buffer mixture, which is mathematically expressed as,
![pH=pK_{a} + log(\frac{[Base]}{[Acid]})](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%20%2B%20log%28%5Cfrac%7B%5BBase%5D%7D%7B%5BAcid%5D%7D%29)
According to the given conditions, the equation will become as follow
![pH=pK_{a} + log(\frac{[Na_{2}HPO_{4} ]}{[NaH_{2}PO_{4}]})](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%20%2B%20log%28%5Cfrac%7B%5BNa_%7B2%7DHPO_%7B4%7D%20%5D%7D%7B%5BNaH_%7B2%7DPO_%7B4%7D%5D%7D%29)
The base and acid are assigned by observing the pKa values of both the compounds; smaller value means more acidic. NaH₂PO₄ has a pKa value of 6.86, while Na₂HPO₄ has a pKa value of 12.32 (not given, but it's a constant). Another more easy way is to the count the acidic hydrogen in the molecular formula; the compound with more acidic hydrogens will be assigned acidic and vice versa.
Placing all the given data we obtain,
Answer:
Fibre , it is a long thin strand or something like thread of material.
Fabric, it is a cloth material made by weaving or knitting threads together.
