Answer:
Ionic bonds form when atoms transfer electrons between each other, forming ions that are electrically attracted to each other forming a bond between them. Sodium chloride (NaCl) is a typical ionic compound. The picture below shows both a sodium and a chlorine ion.
Explanation:
ionic bond
Because of the propensity of sodium to lose an electron and of chlorine to gain an electron, the elements are well suited to bond with one another. This transfer of electrons results in the formation of the ionic bond holding Na+ and Cl– together.
Answer:
the color of the litmus paper will turn into blue color because sodium carbonate is basic in nature
Ice, water, fog/water vapor
Answer:
CFC’s illustrate that technical advances can be a “double-edged” sword as CFC's were made for the advantages but soon or later it came as a disadvantage for environment.
CFC's was discovered with many advantages such as they are stable, non-corrosive, and replacement of harmful ammonia used in refrigerators and air conditioning systems. But soon it is also discovered that CFC's are destroying the upper atmosphere layer called ozone, which is a very big disadvantage for us. CFCs are major contributor to global warming after carbon dioxide.
Hence, it proves that CFC’s shows how technological advancement can be “double-edged” sword.
Answer:
27%
Explanation:
Hello,
The following information is missing, but I found it: "1.92 g of sodium sulfate is produced from the reaction of 4.9 g of sulfuric acid and 7.8 g of sodium hydroxide" so the undergoing chemical reaction is:

Now, to compute the percent yield, we must first establish the limiting reagent to subsequently determine the theoretical yield of sodium sulfate because the real (1.92g) is already given, thus, we consider the following procedure:

- The moles of sodium hydroxide that completely react with 0.05 moles of sulfuric acid are:

As this number is higher than the previously computed 0.05 moles of available sulfuric acid, one states that the sulfuric acid is the limiting reagent. Now, the theoretical grams of sodium sulfate are found via:

Finally, the percent yield turns out into:

%
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