Answer:
0.1 mol
Explanation:
Step 1: Given data
- Volume of the solution of sodium hydroxide (V): 200 cm³
- Molar concentration of sodium hydroxide (C): 0.5 mol/dm³
Step 2: Convert "V" to dm³
We will use the conversion factor 1 dm³ = 1000 cm³.
200 cm³ × 1 dm³/1000 cm³ = 0.200 dm³
Step 3: Calculate the moles (n) of NaOH
The molarity of the NaOH solution is equal to the moles of NaOH divided by the volume of solution.
C = n/V
n = C × V
n = 0.5 mol/dm³ × 0.200 dm³ = 0.1 mol
Answer:
a, b and d are correct.
Explanation:
There are two types of attractive forces in covalent compounds:
- The force that holds the atoms together in a molecule (the covalent bond).
- The force that <u>operates between molecules</u>, called an intermolecular force.
Because intermolecular forces are usually quite weak compared with the forces holding atoms together within a molecule, <u>molecules of a covalent compound are not held together tightly</u>. Consequently, covalent compounds are usually gases, liquids, or low-melting solids.
Most covalent compounds aqueous solutions generally do not conduct electricity, because the compounds are nonelectrolytes.
Answer:
1.7 moles of ethanol would be needed.
Explanation:
* Calculate the moles of ethanol needed to produce 1.70mol of water. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.
First off, we have to state the equation for the reaction.
So we know that;
ethanol + oxygen → acetic acid + water
This leads us to;
C2H5OH + O2 → CH3COOH + H2O
1 1 1 1
To obtain the moles of ethanol needed to produce 1.70mol of water, we look at the stoichiometry of the reaction above.
1 mol of ethanol produces 1 mole of water
x mol of thanol would produce 1.7 mol of water
Thus we have;
1 = 1
x = 1.7
x = 1.7 moles of ethanol would be needed.
Given:
Rivet diameter, 
= 1.872 cm
Hole diameter, 
= 1.870 cm
Temperature, 
= 22 °C
Formula Used:
where,
= coefficient of linear expansion
= change in diameter = 
= change in temperature = 
Solution:
we know that coefficient of linear expansion of steel, = 
Using the above formula :
= \frac{1.870 - 1.872}{1.872\times \T_{2} - T_{1}}[/tex]
= \frac{1.870 - 1.872}{12\times 10^{-6}}}[/tex]
Therefore, the rivet must be cooled to 
Answer:
B
Explanation:
Isotopy is a phenomenon in which there exists two or more kind of atoms of the same element. These atoms have the same number of protons but different mass numbers. That is, they have the same atomic number but differ only by the number of neutrons in the nucleus of the atom. Now, let us apply this information to the options individually:
A. Is wrong, they are not the same element
B. Is correct. they both belong to the same element hydrogen. Infact, they are named protium and deuterium respectively
C is wrong they are not same element
D is wrong They are not elements at all
E. Is wrong, one is an element, the other is a molecule
