Answer:
D. AX + BY -> AY + BX
Explanation:
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
AB + CD → AC +BD
So from given list of reactions option D is correct while others are incorrect.
Other examples:
The reaction between sodium chloride and silver nitrate is double displacement reaction.
NaCl + AgNO₃ → AgCl + NaNO₃
The anion and cations of both reactants exchange. The anion of sodium chloride (Cl⁻) combine with cation of silver nitrate (Ag⁺) and form AgCl. While Anion of silver nitrate combine with cation of sodium chloride and form sodium nitrate.
Answer:
12 mi/h
Explanation:
Step 1: Given data
Step 2: Convert "d" to miles
We will use the conversion factor 1 mi = 1.60934 km.
6 km × 1 mi/1.60934 km = 3.7 mi
Step 3: Convert "t" to hours
We will use the conversion factor 1 h = 60 min.
19 min × 1 h/60 min = 0.32 h
Step 4: Calculate the average speed of the runner (s)
The speed is equal to the quotient between the total distance and the time elapsed.
s = d/t
s = 3.7 mi/0.32 h = 12 mi/h
Answer:
C) 35%
Explanation:
Thymine pairs with adenine. If thymine is 15% then so would adenine be 15%. That leaves the reaminder to be 70%. Cytosine pairs with guanine, thereby, they would each be 35%.
Answer:
Solid
Explanation:
In solid there are strong intermolecular forces present as compared to liquid and gas. This is why solid are in more packed form as compared to liquid and gas. In liquid and gas intermolecular forces are week that's why molecules are away from each other and occupy more space.
Properties of gases:
Molecule of gases randomly move everywhere and occupy all available space.
Gases don't have definite volume and shape and take the shape and volume of container in which it present.
Their densities are very low as compared to the liquid and solids.
Gas molecules are at long distance from each other therefore by applying pressure gases can be compressed.
The very weak inter molecular forces are present between gas molecules.
Properties of Liquid:
Liquid have definite volume but don't have definite shape.
Their densities are high as compared to the gases but low as compared to the solids.
In liquid, molecules are close to each other and have greater inter molecular forces as compared to the gas molecules.
Properties of solids:
Solids have definite volume and shape.
In solids molecules are tightly pack and very close to each other.
Their melting and boiling point are every high.
The densities of solids are also very high as compared to the liquid and gas.
There are very strong inter molecular forces are present between solid molecules.
Answer:
Thus, the radius of the helium atom in nanometers is - 0.031 nm
Explanation:
Given that:-
The radius of the helium atom = 31 pm
Considering the conversion of length in pm to the length in nm as:-
1 pm = 0.001 nm
So,
Applying the above conversion factor in the radius of helium atom as:-
Radius = 
nm = 0.031 nm
<u>Thus, the radius of the helium atom in nanometers is - 0.031 nm</u>
