I need someone to check these True or False questions for me please:
3. Dissolving salt in water is a physical change- F
14. Burning newspaper is a physical change- F
19. The liter is a measure of volume- T
20. The amount of heat and temperature of a substance are the same- F
21. Zero degrees is the freezing point of water on the Fahrenheit scale- F
23. Scientific laws can change- I was kind of stuck on this one because my text book says that "these laws can be reinterpreted" but the internet says they can't be so...F?
24. Mass is the measure of the earth's gravitational attraction- F
29. Rusting of iron is a chemical property- T
38. Scientists use the SI system of measure.- T
Thanks
-MC
3. Dissolving salt in water is a physical change- F
It was Na ions and Cl ions in the solid form; it's Na ions and Cl ions in the dissolved form. physical change
14. Burning newspaper is a physical change- F
I suppose the ACT of burning a newspaper is a physical change but burning a newspaper produces CO2 and water so it is a chemical change.
19. The liter is a measure of volume- T
ok
20. The amount of heat and temperature of a substance are the same- F
ok
21. Zero degrees is the freezing point of water on the Fahrenheit scale- F
ok
23. Scientific laws can change- I was kind of stuck on this one because my text book says that "these laws can be reinterpreted" but the internet says they can't be so...F?
I suppose you could get into a heated argument on this. Certainly, if sufficient data presents itself, laws CAN be changed (reinterpreted is just a euphemism for "laws can be changed but we don't want to admit it" but many will argue that "theit law wasn't well founded so it really wasn't a valid law and we really aren't changing it." I think they can be changed in light of new and relevant data.
24. Mass is the measure of the earth's gravitational attraction- F
OK
29. Rusting of iron is a chemical property- T
OK
38. Scientists use the SI system of measure.- T
That's true, especially if we must; however, not all of us like all of them.
So #3 is T?
Thanks a lot!
-MC
To check these True or False questions, we will go through each statement one by one and provide an explanation for each answer:
3. Dissolving salt in water is a physical change - False
Explanation: When salt dissolves in water, it is considered a physical process rather than a chemical change because no new substances are formed. The salt particles disperse throughout the water, but the salt itself remains chemically unchanged.
14. Burning newspaper is a physical change - False
Explanation: The burning of newspaper is a chemical change because it involves a chemical reaction. During combustion, new substances are formed, such as ash, smoke, and gases (carbon dioxide, water vapor, etc.). Therefore, it is not considered a physical change.
19. The liter is a measure of volume - True
Explanation: The liter is indeed a unit of measurement used to measure volume. It is a metric unit commonly used to measure the volume of liquids and is equal to 1,000 cubic centimeters.
20. The amount of heat and temperature of a substance are the same - False
Explanation: Heat and temperature are related but different concepts. Heat refers to the transfer of thermal energy from one object to another, while temperature measures the average kinetic energy of the particles within a substance. They are not the same thing, so this statement is false.
21. Zero degrees is the freezing point of water on the Fahrenheit scale - False
Explanation: On the Fahrenheit scale, the freezing point of water is 32 degrees Fahrenheit. Zero degrees Fahrenheit is the point where a specific mixture of water, ice, and salt freezes, but it is not the standard freezing point of pure water.
23. Scientific laws can change - False
Explanation: Scientific laws are fundamental principles or relationships that have been extensively tested and proven. While scientific theories and models can change due to new evidence or improved understanding, scientific laws, once established, do not change. Therefore, this statement is false.
24. Mass is the measure of the Earth's gravitational attraction - False
Explanation: Mass is a measure of the amount of matter in an object and is independent of gravity. Weight, on the other hand, is the measure of the gravitational force acting on an object. Therefore, mass is not a measure of the Earth's gravitational attraction, so this statement is false.
29. Rusting of iron is a chemical property - True
Explanation: Rusting is a chemical process that occurs when iron reacts with oxygen and moisture, forming iron oxide (rust). As rusting involves a chemical reaction and a new substance is formed, it is considered a chemical property.
38. Scientists use the SI system of measure - True
Explanation: The SI system (International System of Units) is the globally accepted system of measurement used in science. It provides a standardized set of units for physical quantities, facilitating consistency and precision in scientific measurements. Therefore, this statement is true.
I hope this helps in checking your True or False questions. If you have any further questions, feel free to ask!