The ____ _____ of an element includes atomic number plus the number of neutrons.
How does heat flow when you place an ice cube in your hand?
Suppose a lab group reports a percent yield of sand of 105%. Is it really possible to collect more sand than was originally present? What is a possible explanation for the “extra” product? Do not consider calculation mistakes; think about the procedure used.
A population expert makes a graph to show the future rates of population growth in various countries. Which is necessary a source of error for him?
Exothermic reactions are favored because they release heat to the environment. Would an exothermic reaction be more favored or less favored if it were carried out within a superheated chamber?
No, an exothermic reaction will not be favored or less favored if it were carried out within a super heated chamber. In the super heated chamber the heat will flow back to the reaction( considering heat emitted by the reaction is less than the heat in a super heated chamber). So, the reaction will shift backward instead, the product will again change into reactant.
If the molecular weight of a semiconductor is 27.9 grams/mole and the diamond lattice constant is 0.503 nm, what is the density of the semiconductor in grams/cc ? Two significant digits, fixed point notation.
The given data is as follows.
Mass = 27.9 g/mol
As we know that according to Avogadro's number there are atom present in 1 mole. Therefore, weight of 1 atom will be as follows.
1 atoms weight =
In a diamond cubic cell, the number of atoms are 8. So, n = 8 for diamond cubic cell.
Therefore, total weight of atoms in a unit cell will be as follows.
Now, we will calculate the volume of a lattice with lattice constant 'a' (cubic diamond) as follows.
Formula to calculate density of diamond cell is as follows.
or, = 0.0029 g/cc (as 1 )
Thus, we can conclude that density of given semiconductor in grams/cc is 0.0029 g/cc.
Tornados and hurricanes develop over
High pressure systems
List three examples of physical properties. (4 points)
What type of gloves protects your hands from hazardous chemicals? A. Latex Gloves B. Padded Cloth Gloves C. Vinyl or Neoprene Gloves
Answer: Option (c) is the correct answer.
Vinyl or neoprene gloves provide protection to hands against a wide range of chemicals. They are resistant towards oils, organic acids, alkalies, grease, and many other solvents.
These gloves help hands in completing multiple tasks and have high density and tear resist-ability.
Whereas latex gloves are not good for working with non-water solution hazardous chemicals. On the other hand, padded gloves can absorb chemicals therefore, they can harm the skin. Hence, they are not suitable to deal with hazardous chemicals.