Group 7A are halogens
If you look at a periodic table, these elements include F, Cl, Br, I, and At. Some well known salts are KCl and NaCl (better known as table salt!)
If the mass of all of the products in a chemical reaction is equal to 100g then the mass of the reactants in that same reaction had to have had a mass of 100g this is due to the law of conservation of matter stating matter cannot be created or destroyed in a chemical reaction.
Answer:
a) 
b) 
Explanation:
From the question we are told that:
initial Concentration 
Final Concentration 
Final volume needs 
Generally the equation for Volume is mathematically given by
Therefore
The volume of buffer needed is
Answer:So far scientists have not found a way to determine the exact age of the Earth directly from Earth rocks because Earth's oldest rocks have been recycled and destroyed by the process of plate tectonics. If there are any of Earth's primordial rocks left in their original state, they have not yet been found.
Explanation:
<u>Out of all given options, Hubble's findings supported the big bang theory are as follows:
</u>
- The universe formed from a central point.
- Most galaxies in the universe are moving away from Earth.
- There are billions of galaxies in the universe, not just one.
Option C, D, and E
<u>Explanation:
</u>
According to big bang theory, the universe is increasing its region of occupancy in free space. As it is known that the universe is composed of several galaxies. So this spreading of the universe is nothing but spreading of galaxies.
And this is confirmed from Hubble’s findings using Hubble’s telescope. As they have observed that the speed at which the galaxies are travelling in free space has been increased at a faster rate.
So, the galaxies are used to move away from Earth with time at a faster rate which confirms the big bang theory of universe formation. Also, in simple words, universe started from big bang according to cosmology' standard theory, it’s just moves from everything else.
