Ca №20
N(e)=20
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At the center of every atom lies a small, dense "nucleus" that is positively charged.
Atom is the smallest unit of matter. It is made up of electrons, protons and neutrons. Electrons are negatively charged particles that are found scattered in different energy levels outside the nucleus. Protons are positively charged particles present inside the nucleus. Neutrons do not carry charge and found inside the nucleus. Thus, protons and neutrons make up the nucleus of an atom. Since, protons are positively charged and neutrons are uncharged particles, the charge of nucleus becomes positive.
Answer:PH2=0.994atm, mass of zinc=0.606g
Explanation:
Equation for the reaction is written as;
Zn(s) + 2HCl(aq) - ZnCl2(aq) + H2(g)
V= 240ml = 0.240L
T= 30.8oC = 303.8K
Ptotal= 1.036atm
Pwater = 32mmHg at 30oC = 0.042atm
Therefore
PH2 = Ptotal - Pwater
= 1.036-0.042atm
=0.994atm
But PV= nRT
n = PV/RT
= 0.994x0.240/0.0821x303.8
= 0.24/24.94
=0.009324moles
For the grams of zinc
n=mass in grams/molar mass
Mass in grams = no of moles x molar mass
=0.009324x65 = 0.606g
