Answer:
B) a substance's color and odor changed Explanation: A signal that a chemical change has occurred is when its odor (its smell) or its appearance has changed.
The hydrogens and oxygen of a water molecule are held together by covalent bonds.
<h3>
What are covalent bonds?</h3>
A covalent bond is an electron exchange that causes the production of electron pairs between atoms. Covalent bonding is a stable equilibrium of the attractive and repulsive forces between two atoms that occurs when they share electrons.
Bonding pairs or sharing pairs are other names for these electron pairs. Because electrons are shared among several molecules, each atom can reach the equivalent of a full valence shell, resulting in a stable electronic state.
In organic chemistry, covalent bonds are much more common than ionic bonds. Covalent bonds unite the atoms in a single water molecule, whereas hydrogen bonds join two water molecules. Water develops a covalent bond when oxygen shares an electron with each hydrogen atom.
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Can u explain it more plz.
<span>By definition, the first ionization energy is the energy required to remove the most loosely held electron from one mole of gaseous atoms to produce 1 mole of gaseous ions each with a charge of 1+. </span><span />
Answer:
40%
Explanation:
Calculate the percent of the mass that is carbon:
