False. An increase in temperature is an exothermic reaction. However, when a temperature decreases this is known as an endothermic reactionz
We have been given the condition that carbon makes up 35%
of the mass of the substance and the rest is made up of oxygen. With this, it
can be concluded that 65% of the substance is made up of oxygen. If we let x be
the mass of oxygen in the substance, the operation that would best represent
the scenario is,
<span> x = (0.65)(5.5 g)</span>
<span> <em> </em><span><em>x =
3.575 g</em></span></span>
The molar mass (atomic weight ) of sodium is 23.0 grams/mole and the molar mass of sodium azide, NaN3 , is the mass of sodium, 23.0 gram/mole added to the molar mass of three atoms of nitrogen (14.0 x 3 = 42 gram/mole) which equals 65.0 grams/mole. The percentage of sodium is 23.0 /65.0 x 100 % = 35 %
Answer:
See Explanation
Explanation:
Metallic bonds involve attraction between electrons and positively charged metal ions. The metals are ionized and electrons form a sea of valence electrons. These loosely bound electrons surround the nuclei of the metals.
The presence of this sea of electrons explains the fact that metals conduct electricity and heat due to the free valence electrons.
Due to the nature of the bonding between metal atoms,metals are malleable and ductile.
Due to the strong electrostatic interaction between metal ions and electrons, the metallic bond is very strong and is very difficult to break thereby accounting for the greater strength of metals as the size of the metallic ion decreases.
