We are given with the mass of pure iron that reacts with oxygen to form an oxide which has a given mass as well. the mass of oxygen reacted is 8.15-6.25 g or 1.9 grams. THen we convert the mass of the reactants to moles. Iron is equal to 0.1119 moles and oxygen is equal to 0.1188. We divide each number to the less amount. Hence iron is 1 and oxygen is approx 1. The empirical formula hence is FeO or ferrous oxide or Iron (II) oxide.
The answer is C. because it gives up two electrons.
Answer: A) Storing experimental samples
Explanation:
It is a common piece of laboratory glassware that can be made of glass or plastic and is opened at the top and closed at the bottom.
It cannot be used for measurements because there is no graduation indicating the volume.
Althought it can contain extra chemicals left over from an experiment, it is not the main proposal of the glassware that is to store samples.
It cannot be used in a microscope and the object for that is a microscope slide.
Answer:
Sodium.
Explanation:
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is ²³Na.
Substitution Reactions are those reactions in which one nucleophile replaces another nucleophile present on a substrate. These reactions can take place via two different mechanism i.e SN¹ or SN². In SN¹ substitution reactions the leaving group leaves first forming a carbocation and nucleophile attacks carbocation in the second step. While in SN² reactions the addition of Nucleophile and leaving of leaving group take place simultaneously.
Example:
OH⁻ + CH₃-Br → CH₃-OH + Br⁻
In above reaction,
OH⁻ = Incoming Nucleophile
CH₃-Br = Substrate
CH₃-OH = Product
Br⁻ = Leaving group
Organic reactions are typically slower than ionic reactions because in organic compounds the covalent bonds are first broken, this breaking of bonds is a slower step, while, in ionic compounds no bond breakage is required as it consists of ions, so only bond formation takes place which is a quicker and fast step.