Answer:
B. The number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula.
Explanation:
It is not always true that the number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula.
The chemical formulae of a compound are of two main types;
- The empirical formula is that which expresses the composition of a compound in the simplest whole number ratio.
- The molecular formula shows the actual ratio of the atoms in a compound.
Sometimes the number of atoms in the molecular and empirical formula can be the same.
Also, the number of atoms in the molecular formula is always greater than that of the empirical formula when they are not the same.
The answer is (4) taxing the colonies without representation in Parliament
This set off the Revolutionary War, and the slogan "no taxation without representation" became famous.
Answer:
317.6 mL
Explanation:
Step 1: Write the balanced neutralization equation
MgO + 2 HCl ⇒ MgCl₂ + H₂O
Step 2: Calculate the mass corresponding to 640.0 mg of MgO
The molar mass of MgO is 40.30 g/mol. The moles corresponding to 640.0 mg (0.6400 g) of MgO are:
0.6400 g × (1 mol/40.30 g) = 0.01588 mol
Step 3: Calculate the moles of HCl that react with 0.01588 moles of MgO
The molar ratio of MgO to HCl is 1:2. The moles of HCl are 2/1 × 0.01588 mol = 0.03176 mol
Step 4: Calculate the volume of 0.1000 M HCl that contains 0.03176 moles
0.03176 mol × (1 L/0.1000 mol) = 0.3176 L = 317.6 mL
For sig figs, you count the total number of numbers that aren’t 0, you only count 0 if they are after a decimal point. since there is not a decimal point, there are 2 significant figures, answer A
