Biết PTK của một hợp chất tạo nên từ nguyên tố B(II) và nhóm (PO4) có phân tử khối 310 đvC. a- Tìm nguyên tố B.
b- Viết CTHH hợp chất tạo bởI NTHH B và các nhóm nguyên tử còn lại là : sunfat , cacbonat, nỉtrat , hiđroxit.

Which statement about hf is true? it is zero for any compound in its standard state. it is positive when the bonds of the product store more energy than those of the reactants. it is negative when a compound forms from elements in their standard states. it is zero for any element that is in the liquid state.

Which process results in the release of energy stored in the products of photosynthesis? a. polymer synthesis b. depolymerization c. digestion d. cellular respiration

In what way do investigations build scientific knowledge? the results of investigations lead to questions that cannot be tested. they reflect the opinions and social values of scientists, ensuring valid information. the results of investigations lead to new questions, which lead to new investigations. they are not influenced by the research of earlier scientists, so they are able to address gaps in understanding.i