D. toxic chemical used to control pest population.
ΔH(reaction) = ΔH(formation of products) - ΔH(formation of reactants)
ΔH(reaction) = ( 1*ΔH(Pb(s)) + 1*ΔH(CO2(g)) ) - ( 1*ΔH(PbO(s)) + 1*ΔH(CO(g)) )
ΔH(reaction) = ( 0 + -393.5 ) - ( ΔH(PbO(s)) + -110.5 )
ΔH(reaction) = -283 - ΔH(PbO(s))
-131.4 = -283 -ΔH(PbO(s))
ΔH(PbO(s)) = -151.6 kJ
So, the best answer is A.
Answer:
1.30mL
Explanation:
The equation for the reaction is given below:
H2SO4 + 2KOH —> K2SO4 + 2H2O
From the equation above we obtained the following:
Mole of acid (nA) = 1
Mole of base (nB) = 2
The following data were obtained from the question:
Mb = 0.00945M
Vb =?
Va = 50mL
Ma = 1.23 × 10^−4M
Using MaVa / MbVb = nA/nB, we can calculate the volume of KOH as illustrated below:
MaVa / MbVb = nA/nB
(1.23 × 10^−4 x 50)/0.00945xVb = 1/2
Cross multiply to express in linear form
1.23 × 10^−4 x 50 x 2 = 0.00945xVb
Divide both side by 0.00945
Vb = (1.23 × 10^−4 x 50 x 2) /0.00945
Vb = 1.30mL
1) All matter is made of atoms. Atoms are indivisible and indestructible.
2) All atoms of a given element are identical in mass and properties
3) Compounds are formed by a combination of two or more different kinds of atoms.
4) A chemical reaction is a rearrangement of atoms.
1 and 2 were proved wrong.
The answer would be 0.25 g/mL.
I determined the density by dividing the mass by the volume which gives you the density. D = mass/volume.
<span>6 g / 24 mL = 0.25 g/mL
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