Answer:
Everything that has mass and takes up space is matter. Every day, you find something usual that either does't have mass or else don't take up space. Those things are non-matter. Basically, any type of energy or any abstract concept is an example of something that does not have matter.
Explanation:
0.075 L * 1.0 M = 0.075 mol HCl
H2 is half of HCl by the coefficients divide 0.075 by 2 and get 0.0375 mol H2 gas
Answer: 0.052torr
Explanation: Please see attachment for explanation
Answer: 
Explanation:
Electron gain enthalpy is defined as energy released on addition of electron to an isolated gaseous atom.
The amount of energy released will be maximum when the tendency to attract electrons is maximum. As flourine has atomic number of 9 and has electronic configuration of 2,7. It can readily gain 1 electron to attain stable noble gas configuration and hence liberates maximum energy.
Answer:
Hornfels most commonly form in the aureole of granitic intrusions in the upper or middle crust. Hornfels formed from contact metamorphism by volcanic activity very close to the surface can produce unusual and distinctive minerals.