The correct options are as follows:
1. A.
A synthesis reaction is a type of reaction in which two or more reactants combine together to form only one product. Synthesis reaction always release energy in form of light and heat, therefore, they are usually exothermic reactions. In the option given in A, nitrogen and nitrogen combine together to form ammonia; this is a synthesis reaction.
2. D
A radioactive half life refers to the amount of time it will take for half of an original radioactive isotope to decay.
In the question given above, the half life of the element is 1000. Thus, in 1000 years only half of the original amount will remain. In another 1000 years only 1/4 of the original amount will remain and in another 1000 years only 1/8 of the original amount will remain. Therefore, it will take 3 half lives before 1/8 of the original sample remain.<span />
Answer:
A catalyst is a chemical substance that alters the rate of chemical reaction not consumed by the reaction. Hence, a catalyst can be recovered chen unchanged at the ends of chemical reaction. Catalyst can be divided into two typ the basis whether it speeds up or slowdowns the rate of chemical reaction. The positive catalyst and negative catalyst.
The atom positions in a general molecule of formula (not shape class) AXn that has shape square pyramidal at the corers of square and one at the above center of the square.
<h3>What is square pyramidal?</h3>
The square pyramidal is a shape geometry of the hybridization in which it consists of one lone pair and 5 bond pairs of electrons that repel each other and due to which the geometry changes from octahedral to square pyramidal.
As atoms are located at the four corners of the planer and one atom at the above center of the planner which is repelled by 4 atoms present at the corner of the planer.
Therefore, the atom positions in a general molecule of formula (not shape class) AXn that has a shape square pyramidal at the corners of the square and one at the above center of the square.
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Regard the principle of utilization of two gas.
Make a consistent control of hardware containing gas.
Make a consistent control of weight diminishing valves giving gas.
No smoking zone.
Answer:
No we can’t cover the earth with one mole of pennies
Explanation:
We can’t cover the earth with one mole of pennies due to the fact that making this possible will require the flattening and extra expansion before it covers the whole surface.
The extra expansion and flattening with result in the loss of intermolecular forces and won’t remain as a solid and form other states of matter which won’t be able to cover the surface.