Answer: Observation is essential in science. Scientists use observation to collect and record data, which enables them to construct and then test theories
Explanation:
Mass number<span> is the </span>number<span> of protons </span>and<span> neutrons in an atom.
</span>Atomic mass<span> is the average </span>mass<span> of all the isotopes of a certain type.</span>
Answer:
This is heating limestone
Explanation:
Process:
limestone is heated strongly. After a while, the limestone begins to go cloudy. Test tube is heated too much that it is beginning to soften it. After removing limewater, test tube cools down, the pressure in the test tube drops and air pressure pushes the cold the liquid into the hot test tube with terrible result.
Products:
Limestone is also known as calcium carbonate and Limewater
Click on the link provided to show the video
https://youtu.be/RLL5rT_DeKc
or search heating calcium carbonate
you will find a video