Chromium , silver, zinc...
According to the law of conservation of mass, the quantity of the elements, involved in chemical reactions does not change. For example,
H2O2 - > H2O + O2
is wrong, because there are two O atoms on the first side of the equation, and three on the other. To correct it, coefficients must be added, until the amount of both H and O atoms is equal on both sides.
2H2O2 - > 2H2O + O2
Answer:
Ionic bond
Explanation:
When Na loses an electron, it becomes positive ion.
When Cl gains an electron, it becomes negative ion.
The electrostatic attraction between these ions is an ionic bond.
HNO3 + Ca —-> H2O + N20 + Ca(NO3)2
Atoms are electrically neutral because they contain equal quantities of positively charged protons and negatively charged electrons. Electrons and protons have equal but opposite charges, so the result is no net charge. Ions are atoms that have gained or lost electrons.