Answer:
12.044 ×10²³ molecules of HCl
Explanation:
Given data:
Number of moles of MgO = 1 mol
Number of molecules of HCl react = ?
Solution:
Chemical equation:
MgO + 2HCl → MgCl₂ + H₂O
with 1 mole of MgO 2 moles of HCl are react.
Number of molecules of HCl react:
1 mole contain 6.022×10²³ molecules
2 mol × 6.022×10²³ molecules / 1 mol
12.044 ×10²³ molecules
Δ H reaction = q / n where q: amount of heat released and n is number of moles of substance.
q = m . C . ΔT where:
m = mass of substance (g)
C = Specific heat capacity (4.18)
ΔT = change in temperature = 24.25 - 23.16 = 1.09
q = 1000 x 4.18 x 1.09 = 4556 J = 4.556 kJ
number of moles (n) = Molarity (M) x Volume (L)
= 0.185 M x 0.07 L = 0.01295 mole
Δ H = q / n = - (4.556 kJ / 0.01295 mole) = -351.8 kJ / mol
Note: it is exothermic reaction (-ve sign) i.e. temperature is raised
Answer:
Fungi are a food source for animals and humans. This point do not apply on fungi.
Explanation:
Roles of fungi:
Penicillin and Cephalosporins are the antibiotics made by fungi. They are natural sources of antibiotics.
Fungi are eaten by animals examples are mushroom, agaricus and some animals even eat poisonous mushrooms.
Fungi destroy by releasing chemicals into the rock and they get iron this way and then deeply burrow the rocks and harming them.
Fungi acts as a decomposer to nourish the soil and improves vegetation.
Many infections are caused by fungus like ringworm infection, candida and Athlete's food are some examples.
Physicist Ernest Rutherford<span> established the nuclear theory of the atom with his </span>gold-foil experiment<span>. When he shot a beam of alpha particles at a sheet of </span>gold foil<span>, a few of the particles were deflected. He concluded that a tiny, dense nucleus was causing the deflections.</span>