Looking at the same nonmetal group on the periodic table, how does the reactivity of an element in period 2 compare to the reactivity of an element in period 4?

a. the period 2 element would be more reactive because the attractive force of protons is stronger when there are fewer neutrons interfering.

b. the period 2 element would be more reactive because the attractive force of protons is stronger when electrons are attracted to a closer electron shell.

c. the period 4 element would be more reactive because the attractive force of protons is stronger when there are more neutrons .

d. the period 4 element would be more reactive because the attractive force of protons is stronger when electrons are attracted to a farther electron shell.

Answer : Option B) The period 2 element would be more reactive because the attractive force of protons is stronger when electrons are attracted to a closer electron shell.

Explanation : The reactivity of the Periods decreases as we go from left to right across a period. The farther to the left and down the periodic chart we go, the easier it is for electrons to be donated or taken away, resulting in higher reactivities of the elements. The attractive force of the protons is found to be stronger when electrons are found to be attracted to a closer electron shell.

Answer is: B. The period 2 element would be more reactive because the attractive force of protons is stronger when electrons are attracted to a closer electron shell.

For example, fluorine (the period 2) is more reactive than bromine (the period 4).

Fluorine (F) is nonmetal with greatest electronegativity, which means it easily gain electrons.

Fluorine jas atomic number 9, which means it has 9 protons and 9 electrons. It gain one electron to form fluorine anion (F⁻) with stable electron configuration like closest noble gas neon (Ne) with 10 electrons.

Electron configuration of fluorine: ₉F 1s² 2s² 2p⁵.

pre-sliced bread is a relatively recent development in baking technology. previous to that, it was always sold in a bakery in daily-made contiguous loaves with no wrapping, and was moderately perishable, usually being used with a day or two (which is why every bakery had a discounted “day-old” bread table.) therefore, pre-sliced bread would grow stale quickly. the hard crust provided a protective layer, and once the exposed dry slice left from the previous cut was removed, the interior was still soft.

what keeps bread soft is the moisture retained in the crumb (the light spongy part that’s not crust). the reason the crust develops is the surface of the dough gets exposed to hot dry air during baking which browns the outer layer and seals it, preventing all the moisture from escaping the dough. longer exposure to air will also eventually cause your bread to lose flavor and become stale.

people were used to cutting slices as they needed them and storing bread in a specially-made wooden or metal breadbox or pail with a lid to preserve it longer, but the first automatically sliced commercial loaves were produced on july 6, 1928, in chillicothe, missouri, using a machine invented by otto rohwedder, an iowa-born, missouri-based jeweler.[1] pre-sliced bread would indeed dry out, were it not for another 20th century technology: the plastic bag. bread could now be pre-sliced, and if the enclosing bag remains sealed as much as possible, the bread will remain soft and fresh for longer than if sitting unwrapped on a shelf or enclosed in a bread box that is not air-tight. sealed packaging meant bread could also be sold on store shelves and eliminate frequent trips to a bakery.

sealing bread in a plastic bag had another effect: the moisture in the loaf will re-distribute into the crust and soften it, which is sometimes more pleasing in a sandwich - especially for children whose teeth might not yet be strong enough to tear through a hard crust. a homemade loaf of bread can be sealed in a bag overnight and the crust will become soft like store-bought sandwich bread.

these were novel changes in how bread was produced and sold, which led to the coining of the phrase “the greatest thing since sliced bread.”