Answer:
SF4 -Covalent bond
BaBr2 - Ionic bond
Ca - Metallic bond
Explanation:
Sulphur and fluorine are non metals. Nonmetal atoms combine by the sharing of electrons. This is also called a covalent combination(bond).
In BaBr2, a metal is combined with a nonmetal. This combination involves a transfer of electrons from the metal to the nonmetal forming an ion pair. This is otherwise called an ionic bond.
Atoms of a metal are held together by strong metallic bonds that involves positively charged cations and a cloud of electrons.
B) some planets revolve backwards
Answer:
The general preparation of esters( for example ethyl ethanoate) is through a process known as ESTERIFICATION.
Explanation:
The formation of an ester by the reaction between an alkanol and an acid is known as esterification. This reaction is extremely slow and reversible at room temperature, and is catalyzed by a high concentration of hydrogen ions.
In the preparation of one of the simpler esters known as ETHYL ETHANOATE the reactants include ethanol(an alcohol) and glacial ethanoic acid(a carboxylic acid) in the presence of concentrated tetraoxosulphate VI acid as a CATALYST. Note that, a catalyst is any substance that is able to increase the rate of a chemical reaction.
The mixture is warmed in a water bath( hot but not boiling) for about 25 minutes. The mixture is poured into a beaker partially filled with a sodium or calcium chloride to remove interacted ethanol. The ethyl ETHANOATE floats on the mixture as oily globules.
Answer:
New volume of gas = 95.93 ml (Approx)
Explanation:
Given:
Old volume of gas = 86 ml
Old temperature = 30°C = 30 + 273 = 303 K
New temperature = 65°C = 65 + 273 = 338 K
Find:
New volume of gas
Computation:
V1T2 = V2T1
(86)(338) = (V2)(303)
New volume of gas = 95.93 ml (Approx)