Answer:
90% to 97% pure tungsten in a matrix of nickel and copper or nickel and iron.
Explanation:
Heavy metal tungsten alloys are 90% to 97% pure tungsten in a matrix of nickel and copper or nickel and iron. The addition of these alloying elements improves both the ductility and machinability of these alloys over non-alloyed tungsten.
Answer: The correct option is (c). The total pressure doubles.
Solution:
Initially, only 4 moles of oxygen gas were present in the flask.
(
) ( according to Dalton's law of partial pressure)
....(1)
= Total pressure when only oxygen gas was present.
Final total pressure when 4 moles of helium gas were added:

partial pressure of oxygen in the mixture :
Since, the number of moles of oxygen remains the same, the partial pressure of oxygen will also remain the same in the mixture.

= Total pressure of the mixture.
from (1)

On rearranging, we get:

The new total pressure will be twice of initial total pressure.
Answer:
Positive
Explanation:
The antibody screen interpretation is positive. That's because of clump formation when antibody reacts with the antigen and agglutination occurs.
It means that the antibodies were present in the sample that react with the antigen present in the test tube.
<span>Heavier atoms make denser materials</span>