Answer: determines the age of sample Carbon-14 is used in radiocarbon dating and radiolabeling. Medically important, a radioactive isotope is carbon-14, which is used in a breath test to determine the ulcer-causing bacteria Heliobacter pylori
The radiocarbon age of a certain sample of unknown age can be determined by measuring its carbon 14 content and comparing the result to the carbon-14 activity in modern and background samples.
Answer:
2.5 moles of N₂ and 7.5 moles of H₂ entered the reaction
Explanation:
In reaction:
N₂(g) + 3 H₂(g) → 2 NH₃(g)
You can see that the stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) requires the following amounts of reagents and are produced:
- N₂: 1 mole
- H₂: 3 moles
- NH₃: 2 moles
The following three rules can apply:
- If 2 moles of NH₃ are produced from 1 mole of N₂ by stoichiometry of the reaction, 5 moles of NH₃ from how many moles of N₂ are produced?

moles of N₂= 2.5
- If 2 moles of NH₃ are produced from 3 moles of H₂ by stoichiometry of the reaction, 5 moles of NH₃ from how many moles of H₂ are produced?

moles of H₂= 7.5
<u><em>2.5 moles of N₂ and 7.5 moles of H₂ entered the reaction</em></u>
Answer:
A precipitation reaction is one in which substances in solution are mixed and an insoluble product is made. The insoluble product is called a precipitate and can be seen as a solid forming in the reaction mixture.
Answer:
20.9%
Explanation:
- The percentage by mass of solution is given by dividing the mass of solute in grams by the mass of solution in grams then multiplying it by 100%.
% Mass of solution = mass of solute/mass of solution × 100%
= (27.0 g/ 129.0 g) × 100%
= 20.93%
= 20.9%
Answer:
Its phosphorus (P)
Explanation:
In writing the electron configuration for Phosphorus the first two electrons will go in the 1s orbital. Since 1s can only hold two electrons the next 2 electrons for Phosphorous go in the 2s orbital. The next six electrons will go in the 2p orbital. The p orbital can hold up to six electrons. We'll put six in the 2p orbital and then put the next two electrons in the 3s. Since the 3s if now full we'll move to the 3p where we'll place the remaining three electrons. Therefore the Phosphorus electron configuration will be 1s22s22p63s23p3.