I believe it’s the Distance Traveled that is the dependent variable, because the smooth wood, rough wood and number of students are all fixed. I’m not sure though! I hope this helps.
The reaction between HNO3 and Ba(OH)2 is given by the equation below;
2HNO3 + Ba(OH)2 = Ba(NO3)2 + 2H2O
Moles of Barium hydroxide used;
= 0.200 × 0.039 l
= 0.0078 Moles
The mole ratio of HNO3 and Ba(OH)2 is 2: 1
Therefore; moles of nitric acid used will be;
= 0.0078 ×2 = 0.0156 moles
But; 0.0156 moles are equal to a volume of 0.10
The concentration of Nitric acid will be;
= (0.0156 × 1)/0.1
= 0.156 M
Answer:
(A) NaOH and Ca(OH)2: Ca(OH)2
(B) MgCl2 and MgF2: MgF2
(C) Agl and KI: AgI
(D) NH4Cl and PbCl2: PbCl2
Explanation:
We need to see the solubility in water, at similar temperatures, for each compound and see which one is less soluble than the other:
NaOH: 1000 g/L (25 °C)
Ca(OH)2: 1.73 g/L (20 °C)
MgCl2: 54.3 g/100 mL (20 °C)
MgF2: 0.013 g/100 mL (20 °C)
Agl: 3×10−7g/100mL (20 °C)
KI: 140 g/100mL (20 °C)
NH4Cl: 383.0 g/L (25 °C)
PbCl2: 10.8 g/L (20 °C)
After the comparison made we can conclude that the less soluble, after saturation of water, will precipitate first.
Answer:
POLAR COVALENT
Explanation: A polar covalent bond is a covalent bond in which the atoms have an unequal attraction for electrons and so the sharing is unequal. In a polar covalent bond, sometimes simply called a polar bond, the distribution of electrons around the molecule is no longer symmetrical.
