How does hydrogen bonding affect water as it becomes colder and eventually freezes?
It creates tight spaces between water molecules.
It allows water molecules to freeze in random patterns.
It makes ice float on top of water instead of sink.
It causes ice to become more dense than water.
The correct answer is: It makes ice float on top of water instead of sink.
Hydrogen bonding occurs between water molecules due to the attraction between the positively charged hydrogen atom of one water molecule and the negatively charged oxygen atom of another water molecule. When water cools and eventually freezes, these hydrogen bonds become stable and organized, causing the water molecules to arrange themselves in a hexagonal lattice structure. This arrangement creates an open and less dense structure of ice compared to liquid water, resulting in ice having a lower density. Due to this lower density, ice floats on top of water rather than sinking, which is a significant effect of hydrogen bonding on water as it becomes colder and freezes.
What is a pure substance made of positive and negative ions in a fixed ratio called? (1 point)
O a hydrogen bond
O a polar molecule
O an ioninic compound
O an atom
The correct answer is: an ionic compound.
What is true about boiling?
O The boiling point of acetone is higher than the boiling point of water.
O At sea level, water can boil at any temperature.
O Water boils at a higher temperature at higher altitudes.
O The boiling point of a liquid depends on atmospheric pressure.
The correct answer is: The boiling point of a liquid depends on atmospheric pressure.
Boiling is the process in which a liquid converts into a gas at a specific temperature, known as the boiling point. The boiling point of a liquid is influenced by the atmospheric pressure exerted on the liquid's surface. At higher elevations or lower atmospheric pressures, the boiling point of a liquid decreases. Conversely, at lower elevations or higher atmospheric pressures, the boiling point of a liquid increases. Therefore, the boiling point of a liquid is dependent on the surrounding atmospheric pressure. The other options mentioned are not generally true about boiling.
Where does water boil the fastest? (1 point)
O on top of a mountain
O on a boat in the ocean
O on top of a skyscraper building
O on top of a hill
The correct answer is: on top of a mountain.
Water boils faster on top of a mountain compared to other locations because the atmospheric pressure decreases with increasing altitude. At higher altitudes, the atmospheric pressure is lower, which results in a lower boiling point for water. This lower boiling point means that water can reach its boiling temperature and convert into a gas more quickly. Therefore, water boils faster on top of a mountain compared to other locations at lower altitudes.
How could you describe the changes that happen when carbon changes form from graphite to diamond?
It is a chemical change, which could change some of the intensive and extensive properties of the carbon.
It is a physical change, which could change some of the intensive and extensive properties of the carbon.
It is a chemical change, but the intensive and extensive properties of carbon will be maintained.
It is a physical change, but the intensive and extensive properties of carbon will be maintained.
The correct answer is: It is a physical change, but the intensive and extensive properties of carbon will be maintained.
The transformation of carbon from graphite to diamond involves a physical change rather than a chemical change. In this process, the carbon atoms rearrange their structure, but there is no change in the chemical composition of carbon. Both graphite and diamond consist entirely of carbon atoms, but the difference lies in their arrangement. Graphite forms layers of hexagonal rings that can easily slide past each other, while diamond forms a three-dimensional network of tightly bonded carbon atoms. Despite this structural change, the intensive and extensive properties of carbon, such as its melting point, boiling point, density, and mass, remain the same.