Earthquake is a shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's lithosphere that creates systemic waves. These systemic waves are vibrations that travel through the earth carrying the energy released during an earthquake. A seismic gap is the area along a fault where there has not yet been any earthquake activity for a long period of time.
1. The reaction for this would be:
Sn + 4 HNO₃ → SnO₂ + 4 NO₂ + 2 H₂O
The first observation would be bubbling of the solution and brown acrid smoke is produced due to the presence of NO₂ gas. Another observation would be the presence of a white solid which is SnO₂.
2. Heating was required to get rid of the H₂O. When all moisture is gone, you weigh the sample. Afterwhich, you further heat it to get ride of the oxygen. By doing this, you would know the individual mass of each element. Then, you can solve for the empirical formula of the oxide of tin.
B. Electrical, chemical, thermal, mechanical.
Turning the ignition switch on sends an electrical signal, which starts the chemical combustion of the fuel. This gets the engine going, which produces heat (thermal).
Approximately 1,5.1023 molecules
<h3>
Question #1:</h3>
False.
Melting is a type of chemical change.
<h3>Question #2:</h3>
True.
If the substance's atoms change in any way, it is a chemical change.
<h3>Question #3:</h3>
True.
If a substance is broken or torn, it's still the same substance. (Take tearing paper, for example)
<h3>Question #4:</h3>
False.
Take boiling water for example, when you boil water, it is still water, right?
<h3>Question #5:</h3>
False.
<em><u>Every</u></em> chemical or physical change in matter includes change in energy. <u><em>Not most.</em></u>
<h3>
Question #6</h3>
True.
Hydrogen peroxide (H2O2), has turned into water (H2O) and oxygen (O). The substance has change chemically, therefore it is an chemical change.
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I hoped this helps! If you have any questions, feel free to ask! ^^