Predict which pure substance has the following chemical and physical properties: white solid at room temperature, high melting point, soluble in water, highly conductive when dissolved in water, reactive with acids, and high pH.
A)
zinc oxide
B)
sodium hydroxide
C)
molecular oxygen
D)
hydrochloric acid
What's giving you trouble with this problem? The process of elimination should get the answer. O2, for example, you know is a gas, hydrochloric acid you know is an acid so it has a low pH, etc.
The answer is B.Sodium chloride.
D. Hydrochloric acid
Sodium hydroxide
To predict which pure substance matches the given chemical and physical properties, we will analyze each option:
A) Zinc oxide: Zinc oxide is a white solid at room temperature and has a high melting point. However, it is not soluble in water, and when dissolved, it does not exhibit high conductivity or react with acids. It also does not have a high pH.
B) Sodium hydroxide: Sodium hydroxide meets most of the given properties. It is a white solid at room temperature with a high melting point. It is highly soluble in water and exhibits high conductivity when dissolved in water. It is also reactive with acids and has a high pH. Thus, sodium hydroxide seems like a good match.
C) Molecular oxygen: Molecular oxygen is a gas at room temperature, so it does not satisfy the property of being a white solid. Additionally, it does not have a high melting point, nor is it soluble in water. It does not exhibit conductivity when dissolved in water or react with acids. Lastly, it does not have a high pH.
D) Hydrochloric acid: Hydrochloric acid is a colorless liquid at room temperature, so it does not meet the requirement of being a white solid. It does not have a melting point, as it evaporates. It is highly soluble in water and exhibits high conductivity when dissolved, but it does not react with acids and does not have a high pH.
Therefore, option B, sodium hydroxide, seems to be the best match for all the given properties.