Mento Floss

The Mentos-and-soda geyser effect revealed a few months ago has now spawned a contest on YouTube. Eggheads that we are, we figured that to win we'd have to first understand the mechanisms of the explosion -- so we tracked down a science-fair style explanation:

At first glance, it might seem as if a chemical reaction is taking place. Perhaps the Mentos are alkaline and the soda (despite its name) is acidic. That would make the whole thing a variation on my all-time favorite science bit: the baking soda and vinegar volcano. But a quick read of Mentos ingredients reveals precious little alkali...

The water molecules in the soda attract each other strongly but equally throughout the Diet Coke when undisturbed by frisky Mentos. This attraction enables the soda makers to pump extra carbon dioxide into the liquid and keeps all the gas from bubbling out immediately because it takes even more extra energy to push the water molecules apart.

Dropping a Mentos (or, as in the demonstrations above, a slew of Mentos) into the soda breaks the surface tension in two ways. First, the candy is uneven on a microscopic level. These tiny bumps and pits make it easier for bubbles to form because the surface tension is suddenly spread out over a wider area. ... The makeup of the Mentos is also helping here. Gum arabic--an oily gum derived from the acacia tree--and the coconut oil contribute to the effect by paradoxically making the water molecules even more strongly attracted to one another than usual. Remember, oil and water don't mix.

If you don't have any Mentos handy, you can always enter our stupid-sports contest instead; you've got 27.5 hours left.

Maynard L. Parker/Courtesy of The Huntington Library in San Marino, California
The Concept of the American 'Backyard' is Newer Than You Think
A home in Long Beach, California, in the 1950s.
A home in Long Beach, California, in the 1950s.
Maynard L. Parker/Courtesy of The Huntington Library in San Marino, California

Backyards are as American as apple pie and baseball. If you live in a suburban or rural area, chances are good that you have a lawn, and maybe a pool, some patio furniture, and a grill to boot.

This wasn’t always the case, though. As Smithsonian Insider reports, it wasn’t until the 1950s that Americans began to consider the backyard an extension of the home, as well as a space for recreation and relaxation. After World War II, Americans started leaving the big cities and moving to suburban homes that came equipped with private backyards. Then, after the 40-hour work week was implemented and wages started to increase, families started spending more money on patios, pools, and well-kept lawns, which became a “symbol of prosperity” in the 1950s, according to a new Smithsonian Institution exhibit.

A man mows his lawn in the 1950s
In this photo from the Smithsonian Institution's exhibit, a man mows his lawn in Long Beach, California, in the 1950s.
Maynard L. Parker/Courtesy of The Huntington
Library in San Marino, California

Entitled "Patios, Pools, & the Invention of the American Back Yard," the exhibition includes photographs, advertisements, and articles about backyards from the 1950s and 1960s. The traveling display is currently on view at the Temple Railroad & Heritage Museum in Temple, Texas, and from there it will head to Hartford, Connecticut, in December.

Prior to the 1950s, outdoor yards were primarily workspaces, reports. Some families may have had a vegetable garden, but most yards were used to store tools, livestock, and other basic necessities.

The rise of the backyard was largely fueled by materials that were already on hand, but hadn’t been accessible to the average American during World War II. As Smithsonian Insider notes, companies that had manufactured aluminum and concrete for wartime efforts later switched to swimming pools, patio furniture, and even grilling utensils.

A family eats at a picnic table in the 1960s
A family in Mendham, New Jersey, in the 1960s
Molly Adams/Courtesy of the Smithsonian Institution, Archives of American Gardens, Maida Babson Adams American Garden Collection

At the same time, DIY projects started to come into fashion. According to an exhibit caption of a Popular Mechanics article from the 1950s, “‘Doing-it-yourself’ was advertised as an enjoyable and affordable way for families to individualize their suburban homes.” The magazine wrote at the time that “patios, eating areas, places for play and relaxation are transforming back yards throughout the nation.”

The American backyard continues to grow to this day. As Bloomberg notes, data shows that the average backyard grew three years in a row, from 2015 to 2017. The average home last year had 7048 square feet of outdoor space—plenty of room for a sizable Memorial Day cookout.

[h/t Smithsonian Insider]

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