Answer:
- <u><em>Magnesium and fluorine.</em></u>
Explanation:
<em>Ionic compounds</em> are formed by the electrostatic attraction of cations and anions.
Cations, positive ions, are formed when atoms lose electrons, and anions, negative ions, are formed when atoms gain electrons.
When two different atoms have similar atraction for electrons (electronegativity) they will not donate to nor catch electrons from each other, so cations and anions will not be formed. Instead, the atoms would prefer to share electrons forming covalent bonds to complete their outermost shell (octet rule).
Then, in order to form ionic compounds the electronegativities have to substantially different. This situation does not happen between two nonmetal elements, which nitrogen and sulfur are. Then, you can predict safely that nitrogen and sulfur will not form an ionic compound.
Ionic compounds, then require the electronegativity difference that exist between some metals and nonmetals. Being magnesium an alkaline earth metal, its electronegativity is very low. On the other hand, fluorine the first element of the group 17, has the highest electronegativity of all the elements.Thus magnesium and fluorine will have enough electronegativity difference to justify the exchange of electrons, forming ions and, consequently, ionic compounds.
Explanation:
Gay-Lussac's law states that the pressure of a given mass of gas varies directly with the absolute temperature of the gas when the volume is kept constant. Mathematically, it can be written as: {\displaystyle {\frac {P}{T}}=k}. It is a special case of the ideal gas law.
A graph shows a relationship between two variables: independent and dependent. The dependent variable is in the y-axis, while the independent variable is in the x-axis. When it says, plot velocity against time, that means that
velocity is in the y-axis in meters per second, and time is in the x-axis in seconds. An example of a velocity vs time graph is shown in the attached picture. In this example, the motion is in constant acceleration. This is because it is linear, thereby, the slope is constant. If you want to find the instantaneous velocity at a certain time, create a vertical line from the x-axis until it reaches the diagonal line. Then, draw a horizontal line towards the y-axis to know the value of the velocity.
Answer:
D
Explanation:
D. The number of moles of a dissolved substance
If the graph shows that the energy increases as the reaction proceeds, this means that the state of the reaction of the compounds A, B, C and D is exothermic because the system releases heat to the surroundings, thus, resulting to the increase in energy involved in the reaction.
