Answer:
They use hypotheses to guess a result based on what they already know. Observations are used to record the results of an experiment. Predictions are used to have an expected outcome of a test, thinking the hypothesis is correct. Experiments are used to test the hypothesis.
Answer:
No one is correct. The correct expression is:
Keq = [H₂]² . [O₂]² / [H₂O]²
Explanation:
To build the Keq expression in a chemical equilibrium you must consider the molar concentrations of reactants / products, and they must be elevated to the stoichiometric coefficient.
The balance reaction is:
<u>2</u> H₂O (g) ⇄ <u>2</u> H₂ (g) + O₂ (g)
Keq = [H₂]² . [O₂] / [H₂O]²
In opposite side: <u>2</u> H₂ (g) + O₂ (g) ⇄ <u>2</u> H₂O (g)
Keq = [H₂O]² / [H₂]² . [O₂]
Answer:
B. The number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula.
Explanation:
It is not always true that the number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula.
The chemical formulae of a compound are of two main types;
- The empirical formula is that which expresses the composition of a compound in the simplest whole number ratio.
- The molecular formula shows the actual ratio of the atoms in a compound.
Sometimes the number of atoms in the molecular and empirical formula can be the same.
Also, the number of atoms in the molecular formula is always greater than that of the empirical formula when they are not the same.
ionic bond:
Bond formed when an atom donates its electron and other atom receives those electrons.
polar covalent:
Bond formed by equal sharing of electrons between both the atoms and there is an electronegativity difference between the two atoms.
Nonpolar covalent:
Bond formed by equal sharing of electrons between both the atoms and there is no electronegativity difference between the two atoms.
Metallic:
Formed between two metals.
So the bond between :
Phosphorus and chlorine-polar covalent bond as it is formed by equal sharing of electrons between both the atoms and there is an electronegativity difference between the two atoms.
Potassium and oxygen -ionic bond as here potassium donates its electron and oxygen receives those electrons
Fluorine and fluorine -Non polar covalent bond as formed by equal sharing of electrons between both the atoms and there is no electronegativity difference between the two atoms.
Copper and aluminum-metallic bond as Formed between two metals.
Carbon and fluorine -polar covalent bond as it is formed by equal sharing of electrons between both the atoms and there is an electronegativity difference between the two atoms.
Carbon and hydrogen --Non polar covalent bond as formed by equal sharing of electrons between both the atoms and there is no electronegativity difference between the two atoms.
Aluminum and oxygen--ionic bond as here aluminum donates its electron and oxygen receives those electrons
Silver and copper --metallic bond as Formed between two metals.
