Steel because it is a physical combination of different metals.
Answer:
True
Explanation:
<em>An example of a chemical change is burning a wood log to give a pile of ashes.</em> TRUE. In a chemical change there is a change in the identity of the substances, that is, some substances react (reactants) in order to form other substances (products).
A wood log is made of cellulose and organic compound that react with oxygen to produce carbon dioxide and water mainly.
Answer:
CaO- ionic
InAs-covalent
Al2O3-ionic
Bronze- metallic
Explanation:
CaO and Al2O3 are mostly ionic even though the posses a little covalent character but ionic bonding is the main bonding scheme. Bronze is an alloy of two metals hence it contains a metallic bond. InAs has an electro negativity difference of 0.4 between the atoms so it is a polar covalent bond.
<span>Answer:
A 1.00 L solution containing 3.00x10^-4 M Cu(NO3)2 and 2.40x10^-3 M ethylenediamine (en).
contains
0.000300 moles of Cu(NO3)2 and 0.00240 moles of ethylenediamine
by the formula Cu(en)2^2+
0.000300 moles of Cu(NO3)2 reacts with twice as many moles of en = 0.000600 mol of en
so, 0.00240 moles of ethylenediamine - 0.000600 mol of en reacted = 0.00180 mol en remains
by the formula Cu(en)2^2+
0.000300 moles of Cu(NO3)2 reacts to form an equal 0.000300 moles of Cu(en)2^2+
Kf for Cu(en)2^2+ is 1x10^20.
so
1 Cu+2 & 2 en --> Cu(en)2^2+
Kf = [Cu(en)2^2+] / [Cu+2] [en]^2
1x10^20. = [0.000300] / [Cu+2] [0.00180 ]^2
[Cu+2] = [0.000300] / (1x10^20) (3.24 e-6)
Cu+2 = 9.26 e-19 Molar
since your Kf has only 1 sig fig, you might be expected to round that off to 9 X 10^-19 Molar Cu+2</span>
It is the work of J.J Thomson that directly resulted in the development of an atomic model that has negative electrons stuck within a sea of positive material. His proposal was called the plum pludding model. He is the one who discovered electrons.
