Revision work for chemistry Grade-7 first term.
Revision work for chemistry Grade-7 first term. 1. In 1869 the problem was so lv ed by a Russian chemist ca ll ed ------------------ . Dmitri Mendeleev 2. There a re ------------------------------ groups in the Pe r iod i c Tab l e. 8 3. Pe ri ods are t he ------------------ t he Periodic T ab l e. rows across 4. Group s 1 and 2 are all ------------------ . metals 5. S il ic o n and g e rmanium are c a l l ed -----------------. Semi metals 6. -------------- , are unusual metals. They have low melting points and are very soft. alkali metals 7. The alkali metals get more reactive going ----------- the group. Down 8. Compounds formed by Group 1 metals are usually --------------- solids . white 9. T he transition metals a re ' -------------- ' metals. Typical 10. I ron, cobalt and n...