C. the expansion of the universe is accelerating
The scientist's results is that at a temperature of 35<span>°C, the solubility of the substance in water is 146.2 grams in 200 grams of water. There isn't really a different method to determine the solubility of a substance in water. Another procedure could be that a lesser amount of the substance is used and the water required to dissolve it is determined. The solubility of the substance based on the two procedures can then be compared.</span>
Answer:
See explanation
Explanation:
The question is incomplete because the images of the models are absent. However, i will try to give you a general description of what the correct answer should be.
Beryllium is a member of group 2 in the periodic table. Beryllium has an atomic number of 4. This implies that it has four protons in its nucleus and four electrons in its shells. In a neutral atom, the number of electrons on the shells is equal to the number of protons in the nucleus.
The electronic configuration of Beryllium is 1s2 2s2. This implies that it should have two shells each containing only two electrons each.
Since we are using white foam balls for protons and black foam balls for neutrons, the clear plastic will contain four white foam balls and five black foam balls since the mass number of beryllium is 9 and number of neutrons = mass number - number of protons.
Four blue foam balls hanging from strings will represent the electrons around the nucleus.
Any model that corresponds to the description above is the correct answer.