A catalyst is a substance that speeds up a chemical reaction.
Answer:second law of thermodynamics
Explanation:the second law of thermodynamics states that the total entropy of an isolated system can never decrease over time and is constant if only if all processes are reversible.
Answer:
B) As you move across the row, the number of electrons increases and reactivity also increases.
Explanation:
The periodic table is arranged in a way that if you go across a period, the number of protons, neutrons, and electrons in an element increases. In terms of reactivity, the most reactive elements are the ones which have a high electronegativity. The electronegativity of the elements increases as you travel to the right and upwards on the periodic table.
The electron group arrangement of PH₃ is tetrahedral. The molecular shape is a Trigonal pyramid, and the bond angle is 93°.
<h3>What is the bond angle?</h3>
The angle between the atoms in a compound is known as the bond angle. The degree of the binding angle is specified. There is also the bond length. It is the separation between the two atoms' nuclei.
The bond angle between the atoms of phosphine is 93°. It has one lone pair. The central atom is covered with 4 atoms.
Thus, the electron-group arrangement of phosphine is tetrahedral. The molecular geometry or shape is a trigonal pyramid. The bond angle is 93°.
To learn more about bond angles, refer to the link:
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