The charge would be -2 because there are 2 more electrons than protons, and electrons have a negative charge.
Carbonic acid is produced when a strong acid reacts with the bicarbonate buffer system in the human body.
A substance that is impenetrable by x-rays is described as being radiopaque.
Radiopaque substances will not allow x-rays and or other forms of radiations to pass through them.
Instead, they absorb or block the rays and when used in radiology, they appear white or light gray on photographic films.
Radiopaque materials are applied in generating ultrasound images and other forms of clinical procedures.
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