Which of the following is a reliable way to observe that a chemical change has occurred when two substances come in contact with one another ? (1 point)
monitor for the release of a gas conduct a test to determine the chemical makeup of the molecules test for the release of heat observe a color change
All of the options mentioned are reliable ways to observe that a chemical change has occurred when two substances come in contact with one another. However, the most immediate and easily noticeable observation would be to observe a color change.
The reliable way to observe that a chemical change has occurred when two substances come in contact with one another is to observe a color change.
To determine which of the given options is a reliable way to observe a chemical change, we can examine each option and assess if it correlates with the characteristics of a chemical change.
1. Monitor for the release of a gas: This is an indicator of a chemical change taking place, as the formation or release of gas often accompanies a chemical reaction. For example, if two substances react to produce carbon dioxide gas, bubbles or fizzing may be observed.
2. Conduct a test to determine the chemical makeup of the molecules: While this option may provide insight into the reaction and products formed, it is not necessarily a direct observation of a chemical change. It is more of a post-reaction analysis rather than a method of real-time observation.
3. Test for the release of heat: Heat is often generated or absorbed during a chemical reaction. Consequently, detecting an increase or decrease in temperature can suggest a chemical change. But it's important to note that not all reactions produce significant heat, especially at room temperature.
4. Observe a color change: A change in color is a common and noticeable indication that a chemical change has occurred. Some reactions involve the formation of new substances with distinct colors. However, it should be noted that not all chemical reactions result in a color change.
Based on these assessments, both "monitor for the release of a gas" and "observe a color change" are reliable ways to observe that a chemical change has occurred when two substances come in contact with each other.