The Concentration of Br^- Ion in a Sample of H₂O

question 11

Multiple Choice

The concentration of Br^- ion in a sample of H₂O is 10 ppm. What mass of Br^- ion is present in 300.0 mL of H₂O, which has a density of 1.02 g/mL?

• A) 10 mg
• B) 6.00 mg
• C) 3.00 mg
• D) 3.06 mg
• E) 4.52 mg

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Definitions:

Temporal Summation

Addition of one graded potential to another that occur close in time.

Spatial Summation

Spatial summation refers to the process where multiple synaptic inputs, predominantly from separate neurons, combine within a single neuron, potentially leading to an action potential if threshold is reached.

IPSPs

Short for Inhibitory Postsynaptic Potentials, these are electrical changes in the postsynaptic neuron that make it less likely to generate an action potential, thereby inhibiting the neuron.

Potassium Channels

Protein channels in cell membranes that allow potassium ions to pass in and out of the cell, playing key roles in cell signaling and electrical conductivity.