Which elements have the highest reactivites?
A. B and SI
B. I and Xe
C. F and Cl
D. Al and Ga
C. F and Cl
Which city part represents the smooth endoplasmic reticulum?
A. a factory, which builds the materials used within the cell
B. the airport, which carries materials out of the cell
C. the railroad and its trains, which carry materials within the city
D. the mayor's office, which manages the city
E. the recycling plant, where used materials are broken down for reuse
A. a factory, which builds the materials used within the cell
Place the coefficients into the underlined spaces to balance the chemical equation. Not all coefficients must be used and some may be used more than once.
__ C3H8 (g) + __ O2 (g) ---> _ CO2 (g) + _ H2O (l)
1 2 3 4 5
1 C3H8 (g) + 5 O2 (g) ---> 3 CO2 (g) + 4 H2O (l)
A pond ecosystem is made of plants, fish, algae.
Which phrase describes a population within the ecosystem?
A. an individual plant that lives in the ecosystem
B. all the different species of fish in the ecosystem
C. all the algae of the same species in the ecosystem
C. a set of two species that interact within the ecosystem