Answer:
The first equation
Explanation:
For these problems, it is best to label and record how many of each element are on each side of the equation. The first equation has 1 Ca, 2H, and 2Cl on both sides while the second equation has 3H on the left and 2H on the right making the second equation incorrect.
Answer: Option (3) is the correct answer.
Explanation:
When a more reactive element or atom replaces a less reactive atom then this type of reaction is known as single displacement reaction.
In the given reaction, potassium iodide reacts with fluorine and results in the formation of potassium fluoride and iodine.
Here, fluorine being more reactive displaces iodine from potassium iodide.
Therefore, it is a single replacement or displacement reaction.
Answer:Artificial light from cities has created a permanent "skyglow" at night, obscuring our view of the stars. Here's their map of artificial sky brightness in North America, represented as a ratio of "natural" nighttime sky brightness. In the black areas, the natural night sky is still (mostly) visible.
Explanation:
Answer:
The pair of arrows which represents the relationship of speeds of the two cars is;
The second option as shown in the attached drawing
Explanation:
The given parameters are;
The reading on the speedometer of one car = 20 m/s
The reading on the speedometer of the other car = 72 km/h = 20 m/s
The blue arrow = 20 m/s
Therefore, given that the speeds of both cars are equal (20 m/s = 72 km/h = 20 m/s), the pair of arrows that represent the relationship of speeds of the two cars is two equal length blue arrows which is the second option
The attached diagram showing the pair of arrows that represents the relationship of speeds of the two cars is drawn using Microsoft Visio.