Answer:
These are a part of lab procedures:
1. Write a hypothesis to answer a question.
2. Write a title at the top of a completed lab report.
3. Record the time to complete a chemical reaction.
These are NOT a part of lab procedures:
1. Create a question on the cause of a chemical reaction.
Answer:
electrons exist in specified energy levels
Explanation:
In its gold-foil scattering with alpha particles, Rutherford proved that the plum-pudding model of the atom theorised by Thomson was wrong.
From his experiment, Rutherford inferred that the atom actually consists of a very small nucleus, where all the positive charge is concentrated, and the rest of the atom is basically empty, with the electrons (negatively charged) orbiting around the nucleus at very large distance.
However, Rutherford did not specify anything about the orbits of the electrons. Later, Bohr predicted that the electrons actually orbit the nucleus in specific orbits, each orbit corresponding to a specific energy level. Bohr's model found confirmation in the observation of the emission spectrum lines: when an electron in one of the higher energy level jumps down into an orbit with lower energy, the atom emits a photon which has an energy exactly equal to the difference in energy between the two orbits (and this energy of the photon corresponds to a precise wavelength).
<span>It reacts to the </span>motion<span>. If the mass hanging from the pulley was overwhelmingly heavier than the mass on the ramp, it'll obviously pull the ramp mass up and thus </span>friction<span> would be trying to oppose this and vice versa. </span>
Answer:
oxygen is used up is the answer
Explanation:
These vaporized molecules are drawn up into the flame, where they react with oxygen from the air to create heat, light, water vapor (H2O) and carbon dioxide (CO2).