Answer:
The second column on the periodic table of the chemical elements is collectively called the alkaline earth metal group: beryllium, magnesium, calcium, strontium, barium, and radium. Because the outer electron structure in all of these elements is similar, they all have somewhat similar chemical and physical properties.
Explanation:
Explanation:
When two small nuclei combine together to form a large nuclei then it is known as nuclear fusion.
When nuclei of two hydrogen atoms fuse together then it results in the formation of a helium atom along with the release of lot of energy. This energy is nuclear energy.
This nuclear reaction is as follows.

Thus, we can conclude that nuclear fusion represents nuclear energy.
Answer:
- <u><em>1.7 × 10³ kg of ore.</em></u>
Explanation:
Call X the amount of aluminum ore mined to produce 1.0 × 10³ kg the aluminum metal.
Then, taking into account the yield of the reaction (82 % = 0.82) and the percent of aluminun in the ore (71% = 0.71), you can write the following equation:
- X × 71% × 82% = 1.0 × 10³ kg
↑ ↑ ↑ ↑
(mass of ore) (% of Al in the ore) (yield) ( Al metal to obtain)
You must just simplify, solve and compute:
- X = 1,000 / (0.71 × 0.82) = 1,000 / 0.5822 = 1,717.6 Kg
Round to two significant figures; 1,700 kg = 1.7 × 10³ kg of ore ← answer.
Answer: The empirical formula of the compound becomes 
<u>Explanation:</u>
The empirical formula is the chemical formula of the simplest ratio of the number of atoms of each element present in a compound.
We are given:
Mass of C = 48.38 g
Mass of H = 6.74 g
Mass of O = 53.5 g
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
......(1)
To formulate the empirical formula, we need to follow some steps:
- <u>Step 1:</u> Converting the given masses into moles.
Molar mass of C = 12 g/mol
Molar mass of H = 1 g/mol
Molar mass of O = 16 g/mol
Putting values in equation 1, we get:



- <u>Step 2:</u> Calculating the mole ratio of the given elements.
Calculating the mole fraction of each element by dividing the calculated moles by the least calculated number of moles that is 3.023 moles



- <u>Step 3:</u> Taking the mole ratio as their subscripts.
The ratio of C : H : O = 1 : 2 : 1
Hence, the empirical formula of the compound becomes 