Water Containing High Concentrations of Cations Is Called Hard Water

question 63

Multiple Choice

Water containing high concentrations of cations is called hard water.

• A) Ca²⁺ or Mg²⁺
• B) Na⁺
• C) K⁺
• D) Ca²⁺
• E) Mg²⁺

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Definitions:

Back Propagation

A key algorithm in neural networks used for training, by adjusting weights based on the error rate obtained in the previous epoch.

Neuroplasticity

The brain's ability to reorganize itself by forming new neural connections throughout life, allowing the neurons (nerve cells) in the brain to compensate for injury and disease and to adjust their activities in response to new situations or changes in their environment.

Absolutely Refractory

The state of an axon in the repolarizing period, during which a new action potential cannot be elicited (with some exceptions) because gate 2 of sodium channels, which are not voltage-activated, are closed.

Relatively Refractory

The state of an axon in the later phase of an action potential, during which higher-intensity electrical current is required to produce another action potential; a phase during which potassium channels are still open.