Answer:
A synthesis reaction occurs when two or more reactants combine to form a single product. ... Replacement reactions occur when elements switch places in compounds. In a single replacement reaction, one element takes the place of another in a single compound. In a double replacement reaction, two compounds exchange elements.
The answer is SiO2 is Nonpolar.
Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.

The equation can be written in terms of ions as:

Spectator ions are defined as the ions which does not get involved in a chemical equation or they are ions which are found on both the sides of the chemical reaction present in ionic form.
The ions which are present on both the sides of the equation are potassium and nitrate ions and hence are not involved in net ionic equation.
Hence, the net ionic equation is :

<span>The correct answer is b. Radon. Oxygen, Hyrdrogen, and Boron, are not radioactivel ike Radon and it regenerates quickly meaning that even though it has a short half-life period, it stays for a long time once released. It also has no taste so it's difficult to notice without proper gear because you can't feel it.</span>
In this question, you are given the gasoline density (0.749g/ml) and volume of the gasoline (19.2 gallons). You are asked the mass of the gasoline in pounds. Then you need to change the grams into pounds and the ml into gallons. The calculation would be:
mass of gasoline= density * volume
mass of gasoline= 0.749g/ml * (1 pound/453.592grams) * 3785.41ml/gallon * 19.2 gallon= 120 pounds