Volcanoes release several gases during eruptions. which of these gases has been shown to cause significant cooling of the climate for one or more years after an eruption?
a. sulfur dioxide
b. carbon dioxide
c. hydrogen fluoride
d. water vapor

A. sulfur dioxide

Explanation:

The volcanoes are able to influence the global climate both on the short term and on the long term. The end result can be either cooling off of the climate, or warming up of it, depending on what type of gasses are the volcanoes going to release in the atmosphere, as well as how much of them. The sulfur dioxide is a gas that is released by the volcanoes that causes cooling off of the climate. This gas is going through conversion and becomes sulfuric acid, and it is able to restrict the amount of sunlight reaching the surface of the Earth, as well as increasing the reflective properties of the atmosphere, resulting in a few years of significant cooling of the climate.

gravity causes stares to cluster i think so

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.