The atomic mass is determined by the number of protons and neutrons in a atoms for example oxygen has eight protons and neutrons which gives oxygen and atomic mass of 16
Answer:
- The last option: <u><em>Decrease the volume to increase pressure and to increase concentration.</em></u>
Explanation:
You can support your choice on basis of the collision theory.
According to the collision theory, the chemical reactions happen when the molecules collide with each other, in the correct orientation and with enough kinetic energy to overcome the activation energy.
As consequence, the larger the number of collisions the larger the rate of a reaction.
In the case of a reaction that involves gases, decreasing the volume, will increase the pressure and the concentration (volume is inversely related to both the pressure and the concentration) causing the molecules to be closer to each other and to collide with higher frequency, this is you will expect more collisions, and so an increase on the rate of the reaction. That is expressed by the last choice: decrease the volumen to increase pressure and to increase concentration.
Answer:
0.125
Explanation:
For 250 ml it is 0.5 moles. If you know the Molecular weight of NaCl you multiply with 0.5 to get the answer. Required number of moles =2⋅0.25=0.5 moles.
<h3><u>Answer</u>;</h3>
<h3><u>Explanation</u>;</h3>
- Elements in the periodic table are classified into various categories including alkali metals, alkaline-earth metals, halogens, and noble gases among others.
- <u>Alkali metals are Group 1 elements in the periodic table.</u> They comprise of elements lithium (Li) through francium (Fr). They have similar characteristics and behavior.
- <u>Halogens is another category of elements which is a subset of the nonmetals.</u> They comprise group 17 of the periodic table, from fluorine (F) through Astatine (At). These elements are chemically reactive and reacts with other elements such as group 1 and group 2 element.
Answer:
The heat produced by this reaction is 2887J
Explanation:
The reaction of HCl with NaOH occurs as follows:
HCl + NaOH → H2O + NaCl + ΔH
<em>Where ΔH is released heat due the reaction</em>
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The equation of a coffee cup calorimeter is:
Q = C*m*ΔT
<em>Where Q is heat produced, </em>
<em>C is specific heat of the solution (4.18J/g°C), </em>
<em>m is mass of the solution (50mL + 50mL = 100mL = 100g -Because density is 1g/mL) </em>
<em>and ΔT is change in temperature (28.9°C - 22.0°C = 6.9°C)</em>
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Replacing:
Q = 4.184J/g°C*100g*6.9°C
Q = 2887J
The heat produced by this reaction is 2887J
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