J. J. Thomson discovered electron by performing an experiment using cathode ray tubes. High voltage across is applied across two electrodes at that causes a beam of particles to flow from the the negatively-charged electrode that is cathode to the positively-charged electrode that is anode. Properties of the particles, are tested using two oppositely-charged electric plates around the cathode ray. The cathode ray was deflected away from the negatively-charged electric plate and towards the positively-charged plate. This indicated that the cathode ray was composed of negatively-charged particles. And these negatively charged particles are called electrons.
The correct option is this: THE ORGANISM IS A PROKARYOTES.
There are basically two types of cells, prokaryotic and eukaryotic cells. The prokaryotic cells are primitive cells which contain only a few materials which are not well organised. This type of cells is usually found in microscopic organisms. The cells lack organised nucleus and cell organelles which have membranes.<span />
D the substance is a homogeneous mixture
Usually (ignoring transition metals, as they kinda get trickier), the element's valency can be found out by its group (column) number. Usually, we ignore the transition metal block while counting these columns, so Aluminium is in group 3, for example. Since Aluminium is in group 3, it has 3 valence electrons.
This is an acid – base reaction and this always result a salt and water
in a neutralization reaction. <span>
The salt that is formed will be calcium bromide (calcium
is located in group 2 so calcium bromide has a formula of CaBr2)
so essentially we got:
HBr + Ca(OH)2 ------> CaBr2 + H2O </span>
balancing the elements: <span>
<span>2HBr(aq) + Ca(OH)2(aq) --------> CaBr2(aq) +
2H2O(l)</span></span>