Question 15 Answer and Explanation _ACT June 2014 Form 72C English Section

Passage I

The Triangular Snowflake

[1]

Snowflakes form from tiny water droplets, following a specific process of chemical bonding as they freeze, which results in a six-sided figure. The rare “triangular” snowflake, similarly, confounded scientists for years because it apparently defied the basic laws of chemistry. [A] The seemingly triangular shape of those snowflakes suggests that forming through a different process of chemical bonding. [B] By re-creating snowflake formation, a discovery has revealed to scientists Kenneth Libbrecht and Hannah Arnold the cause of this apparent variation.

[2]

Snowflakes begin to form when water in the atmosphere freezes it causes the water molecules to bond into a hexagonal shape. During the flake’s descent from Earth’s upper atmosphere, other water vapor molecules bumps into the hexagonal structure. Bypassing the liquid water phase, those molecules condense directly onto the established hexagonal pattern. As a result, the flake grows outward into bigger and more complex hexagonal arrangements surrounding the original hexagonal shape at the center of the flake. [C]

[3]

In 2009, Libbrecht and Arnold’s experiments revealed that triangular snowflakes begin with the same process of chemical bonding and forms a hexagonal shape. The triangular shape is an illusion resulting from one significant addition to the process dust.

[4]

Triangular snowflakes begin to form when a tiny dust particle or other such impurity collides with the flake as it falls, thereby pushing one edge upward. [D] The downward edge of the snowflake encounters more wind resistance than the rest of the flake. The greater the pressure from the wind, causes bonds to form quick at this edge than in the rest of the snowflake.

[5]

The resulting snowflake has three long sides and three sides that are so short they are difficult to detect. Although these snowflakes appear to have a triangular shape—they actually have a hexagonal pattern. Such snowflakes offer evidence that even when impurities interfere, the basic laws of chemistry still apply.

15. Suppose the writer’s primary purpose had been to offer an example of a discovery that changed the way scientists viewed the basic laws of chemistry. Would this essay accomplish that purpose?

A. Yes, because it describes how the observation of triangular snowflakes has led scientists to discover that their understanding of the basic laws of chemistry is flawed.

B. Yes, because it describes how scientists have applied the knowledge they’ve gained through studying snowflakes to other areas of chemistry.

C. No, because it focuses on how scientists are struggling to determine how triangular snowflakes are formed.

D. No, because it explains that triangular snowflakes appeared to, but don’t actually, violate the basic laws of chemistry.

Answer and Explanation

Your Answer is

Correct Answer is D

Explanation

The main idea of ??the article is about a phenomenon that seems to violate the laws of chemistry, that is, snowflakes only have three corners, but the facts do not violate it. Item C "Because this article focuses on how scientists are trying to determine the formation of triangular snowflakes" The main point of this article is not about the struggling of scientists, wrong.