Chemistry Practice Questions

1. A major ion in seawater typically has a residence time that is:

a) a few decades
b) several thousand years
c) millions of years
d) near the age of the ocean
2. What property of small particles causes them to sink vertically to the bottom of the ocean?
a) density
b) aggregation
c) terrigenous components
d) biogenic source
3. Coccolithophorids are important __________________ in the ocean because they produce biogenic inorganic sediment in the form of_____________________.

4. After what time, on average, would a parcel of water which had just sunk from the surface to become North Atlantic Deep Water find itself upwelling in the North Pacific?

a) several decades
b) infinite (never)
c) about a thousand years
d) time equal to major ion residence time
5. Surface sediments accumulate on the flanks of the sub-sea mountain range called the East Pacific Rise. The overlying waters have generally low producitivity and the depth is about 3000m. What component is likely to dominate the sediment composition?
a) opal
b) terrigenous particles
c) hydrogenous (authigenic) particles
d) calcium carbonate