The discovery that macroscopic and microscopic phenomena are connected took several hundred years.
A model is a representation of a real life system that serves as a tool for predictions and explanation. Since models serve a predictive purpose, a model’s usefulness depends on the accuracy of its predictions.
The pressure of a gas is caused by the collision of gas molecules with the walls of the container. This was established by the scientist called Daniel Bernoulli.
Avogadro was able to create the term molecule to describe a substance that has independent existence. The discovery that macroscopic and microscopic phenomena are connected took several hundred years. It took several hundred years for scientists to develop current theories, and they are still being revised to this day.
The results of experiments investigating the relationship between microscopic and macroscopic phenomena affect a model of molecular theory in the sense that consistent results support the validity of the model, while inconsistent results indicate the need to modify the model.
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Answer:
1. Potassium, K.
2. Calcium, Ca.
3. Gallium, Ga.
4. Carbon, C.
5. Bromine, Br.
6. Barium, Ba.
7. Silicon, Si.
8. Gold, Au.
Explanation:
Atomic radius can be defined as a measure of the size (distance) of the atom of a chemical element such as hydrogen, oxygen, carbon, nitrogen etc, typically from the nucleus to the valence electrons. The atomic radius of a chemical element decreases across the periodic table, typically from alkali metals (group one elements such as hydrogen, lithium and sodium) to noble gases (group eight elements such as argon, helium and neon). Also, the atomic radius of a chemical element increases down each group of the periodic table, typically from top to bottom (column).
Additionally, the unit of measurement of the atomic radius of chemical elements is picometers (1 pm = 10 - 12 m).
1. Li or K: the atomic radius of lithium is 167 pm while that of potassium is 243 pm.
2. Ca or Ni: the atomic radius of calcium is 194 pm while that of nickel is 149 pm.
3. Ga or B: the atomic radius of gallium is 136 pm while that of boron is 87 pm.
4. O or C: the atomic radius of oxygen is 48 pm while that of carbon is 67 pm.
5. Cl or Br: the atomic radius of chlorine is 79 pm while that of bromine is 94 pm.
6. Be or Ba: the atomic radius of berryllium is 112 pm while that of barium is 253 pm.
7. Si or S: the atomic radius of silicon is 111 pm while that of sulphur is 88 pm.
8. Fe or Au: the atomic radius of iron is 156 pm while that of gold is 174 pm.
2H2O -> 2H2 + O2
Stoichiometric ratio:
2 : 2 : 1
H2O : O2
2 : 1
Mass of 1 mol of H2O = [(2 x 1) + 16] g = 18g
18g of H2O = 1 mol of H2O
90g of H2O = 90g x 1 mol / 18g
= 5 mol of H2O
2 mol of H2O : 1 mol of O2
5 mol of H2O : 5/2 mol of O2
1 mol of O2 = 22.4 L of O2
5/2 mol of O2 = 5/2 mol x 22.4 L / 1 mol
= 56 L of O2
Answer:
CH4 + 2 O2 → CO2 + 2 H2O
Explanation:
There are one mole of O2 on the left side and on the right side there are three moles of O2. And to fix it you would need to make it two moles of O2 to have four molecules of O2 on the left side. Then you would make two moles of H2O to have a total of four moles of O2 on the right. Therefore, CH4 + 2 O2 → CO2 + 2 H2O is the answer.
Ra-226 will go through α decay which means the nucleus of radium-226 will emit a α particle. α particle consists of 2 protons and 2 neutrons. So it will become Rn-222.