This question is asking for an element with 5 valence electrons. Just go to the row it is in (excluding transition metals) and count over.
The answer would be c. P
Metals consist of giant structure of atoms arranged in a regular pattern. The electrons in the outer shell of metal atoms are shared , and are free to move throughout the structure. Therefore the structure is formed by positive charged metal ions held together by a 'sea' of delocalised.
Methane is lighter than air, having a specific gravity of 0.554. It is only slightly soluble in water. It burns readily in air, forming carbon dioxide
and water vapour; the flame is pale, slightly luminous, and very hot.
The boiling point of methane is −162 °C (−259.6 °F) and the melting
point is −182.5 °C (−296.5 °F). Methane in general is very stable, but
mixtures of methane and air, with the methane content between 5 and 14
percent by volume, are explosive. Explosions of such mixtures have been
frequent in coal mines and collieries and have been the cause of many
mine disasters.
Answer:
C
Explanation:
Just look at the reactants.
2AgCl + BaBr2
The first reactant is made of 2 elements.
The second reactant is made of 2 elements.
It can't be a decomposition. At this level there is only one reactant made of 2 elements. Something like
2MgO ===> 2Mg + O2
is a decomposition. One compound breaking down into 2 elements Mg and O.
It can't be a combustion. One of the reactants in a combustion is oxygen. Those equations look like
C3H8 + 5O2 ==> 3CO2 + 4H2O
That would be what a combustion looks like
It can't be a single replacement. They look like
Mg + CuO ===> Cu + MgO
There are elements on both sides of the reaction.
that leaves a double replacement which I wrote about how you distinguish it.
