Density =mass /volume
Volume =1800÷0.79
= 2278.481ml
Answer:
About 512 g.
Explanation:
We are given a sample of P₂Cl₅ that contains 179 grams of phosphorus, and we want to determine the grams of chlroine that is present.
Thus, we can convert from grams of phosphorus to moles of phosphorus, moles of phosphorus to moles of chlorine, and moles of chlorine to grams of chlorine.
From the formula, there are two moles of P for every five moles of Cl. The molecular weights of P and Cl are 30.97 g/mol and 35.45 g/mol, respectively. Hence:
In conclusion, there is about 512 grams of chlorine present in the sample.
Alternatively, we can mass percentages. The mass percent of phosphorus in P₂Cl₅ is:
Because there are 179 grams of phosphorus, the total amount of sample present is:
Therefore, the amount of chlorine present is 691.1 g - 179 g, or about 512 g, in agreement with our above answer.
Answer: (3) silicon
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Silicon (Si)
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: ethane , propanone and water
Answer:
55.9 g KCl.
Explanation:
Hello there!
In this case, according to the definition of molality for the 0.500-molar solution, we need to divide the moles of solute (potassium chloride) over the kilograms of solvent as shown below:
Thus, solving for the moles of solute, we obtain:
Since the density of water is 1 kg/L, we obtain the following moles:
Next, since the molar mass of KCl is 74.5513 g/mol, the mass would be:
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Answe
Explanation:
The answer is reduced effectiveness of pesticides.
Genetic engineering has a great advantage in vaccines production or in a pharmaceutical production of desired proteins, such as insulin, human growth hormone, etc. In plant genetic engineering increased drought and salinity tolerance will help plants survive in difficult conditions.
On the other hand reduced effectiveness of pesticides is a disadvantage of using genetic engineering. Genetically modified plants may develop resistance to pesticides, so pesticides are not effective as expected.