Melting iron would be a physical change
Iron rusting would be a chemical change
Answer:
METHOD 1: (surface area of a solid reactant) METHOD 2: (concentration or pressure of a reactant)
Explanation:
METHOD 1: (surface area of a solid reactant) Increasing the surface area of a solid reactant exposes more of its particles to attack. This results in an increased chance of collisions between reactant particles, so there are more collisions in any given time and the rate of reaction increases.
METHOD 2: (concentration or pressure of a reactant) Increasing the concentration means that we have more particles in the same volume of solution. This increases the chance of collisions between reactant particles, resulting in more collisions in any given time and a faster reaction. As we increase the pressure of reacting gases, we increase the rate of reaction.
Answer:
No. 3 lithium
Explain that lithium has 3 protons and 3 electrons. There are 2 electrons on the first energy level and 1 electron on the second
No. 4 Hydrogen (H) and helium (He) have a valence shell containing one and two electrons respectively. They make up the first period (row) of the periodic table. Their valence electron/s are in the first energy level (n=1) , as is denoted by 1s1 and 1s2 .
<em>That</em><em>'</em><em>s</em><em> </em><em>all</em><em> </em><em>i</em><em> </em><em>dont</em><em> </em><em>know</em><em> </em><em>if</em><em> </em><em>this</em><em> </em><em>is</em><em> </em><em>right</em><em> </em><em>though</em><em>.</em><em> </em>
