Answer:
magnesium metal melts = physical change
magnesium metal ignites = chemical change
Explanation:
<em>Physical changes</em> are those in which the identity of the subtance <u>remains unaltered</u>. No new compounds are formed. They involve generally changes in <u>agreggation states of matter</u>: solid, liquid or gas. The first experiment, in which magnesium metal melts is a physical change because it only changes the state of matter, from solid to liquid, but it is still magnesium metal.
Conversely, <em>chemical changes</em> involve atoms combinations to form new compounds. The second experiment, in which magnesium metal ignites, is a chemical change. After the change, magnesium metal is no longer the metal but a metal oxide.
Answer:
Which sequence of events is required to form a limestone cave where you can walk around and observe cave formations, such as stalactites? (Note: stalactites hang from the ceiling - they have to hold on tight to the roof.)
A geological sequence of events as involving the lowering of the water table to expose cave structures where stalactites and stalagmites form which is described as follows,
Explanation:
1. Acidic percolated water formed cavities of solution beneath the natural water table known as phreatic zone
2. After the passage of time there is a drop in the water table dropped forming caves from cavities
3. These caves, which are air filled voids that contains adequate environment for forming stalactites and stalagmites and where they are found
Answer:
1s², 2s², 2p³
Explanation:
The atomic number of Nitrogen is seven. So it contains seven protons and seven electrons in neutral form. Also, the electronic configuration cited above contains seven electrons among which two electrons are present in first shell and five electrons are present in valence shell respectively.
1. Curiosity-They love to learn 2. Open-mindedness- he accepts criticisms fairly well
3. Rationality- he does not believe in superstitions and think that everything has a scientific explanation
4. Critical Mindedness & Correct Judgement- he does not easily jump to conclusions but tries to verify his results by (if possible) repeating the experiment
5. Intellectual Honesty- does not alter his observations and writes the correct observations he has seen
6. Objectivity-<span> he writes accurate results
Hope This Helped :D</span>
Answer:
Answer B
Explanation:
By definition mixtures are combinations of substances physically prepared and physically separated. Mixtures are classified as 'homogeneous mixtures' and 'heterogeneous mixtures'. For homogeneous mixtures all components are dissolved, with solute evenly distributed throughout the solution and assumes state of solvent. 'Heterogeneous mixtures' have inconsistent properties throughout and solute concentration is not consistent throughout the mixture.