Answer:
D. the mass of one mole of a substance
Explanation:
The molar mass of a substance is the mass in grams of one mole of the substance.
- For an element, the molar mass is the relative atoms mass expressed in grams.
- For example 23g of Na, 40g of oxygen
- For compounds, molar mass is the gram -formula or gram - molecular weight.
- This is determined by the addition of its component atomic masses and then expressed in grams.
Given mass of tungsten, W = 415 g
Molar mass of tungsten, W = 183.85 g/mol
Calculating moles of tungsten from mass and molar mass:
D. Chemical and Physical Properties
Answer:
Different types of isotopes are used for different materials or objects. For radiometric dating, uranium-235 is considered best for it while carbon-14 is used for dating of rocks. It is also used for dating of wood samples.
Explanation:
Carbon-14 and uranium-235 are used for different materials or objects for measuring the age of these materials. These two isotopes are radioactive in nature which means they emit gamma radiations which allow us to find the age of different objects. Carbon-14 has a low half life so it can be used for those objects which are present before thousands of years while uranium-235 is used for materials which are millions of years old due to high half life.
The answer C. Why because homogeneous is one thing not two. one of the same thing.
