Answer:
1. The standard metric unit of length is a meter.
2. A proposed explanation for a scientific problem is a hypothesis.
3. The standard unit of volume is a liter.
4. The curved top surface of a liquid column is the meniscus.
5. A quantity in an experiment that remains unchanges or constant is a controlled variable (control)
6. The amount of matter in an object is mass.
A. 6 NaOH + 2(NH4)3 PO4 -----> 2Na PO4 + 6H2O + 6NH3
b. C2 H6 O + 3O2 ----> 2CO2 + 3H2O
