Answer: 9.27 g of Na
Explanation:Please see attachment for explanation
Answer:
Option D = No, when elements combine to form a new material, they have properties unique to the new materials.
Explanation:
When sodium contact with water it loses its one electron and thus gain positive charge. When there are more sodium atoms present and many atoms do this thus more positive ions are produced and these positive ions repeal each other at high speed and explosion occur.
But when it form compound with other material, it will not showed this behavior.
Example:
Consider the sodium chloride, when it dissolve in water sodium not showed explosion. In sodium chloride sodium already gives its electron to the chlorine and have stable electronic configuration. The sodium present in cationic form. When it dissolve, partial positive charge of water surrounds the Cl⁻ and partial negative charge of water surrounds the Na⁺ ion, ans sodium chloride gets dissolve into water without explosion.
Mass number (A) =protons (p+) + neutrons(n°)
The original or accepted value for the percent by mass of water in a hydrate = 36%
Percen by mass of water in the hydrate determined by the student
in the laboratory = 37.8%
So the difference between the actual and the percent by mass in water determined by student = (37.8 - 36.0)%
= 1.8%
So the percentage of error made by the student = (1.8/36) * 100 percent
= (18/360) * 100 percent
= ( 1/20) * 100 percent
= 5 percent
So the student makes an error of 5%. Option "1" is the correct option.
Answer:
C. C
Explanation:
The heating curve is a graphical representation shows that how different phases of substances change as it is influenced by the increase in temperature or heat.
Section A represents solid phase, Section B represents solid-liquid phase, section C represents liquid phase, section D represent liquid-gas phase and section E represents gas phase.
Section C of the graph shows the liquid phase of the substance gaining kinetic energy. During Phase C, heat energy is absorbed and liquid particles gain kinetic energy to change into gas form that is section E.
Hence, the correct option is C.C.
