Answer:
The answer to your question is 0.32 moles of water are needed.
Explanation:
Data
mass of CaC₂ = 10 g
mass of water = ?
Process
1.- Write the balanced reaction
CaC₂ + 2H₂O ⇒ C₂H₂ + Ca(OH)₂
Reactant Element Product
1 Ca 1
2 C 2
4 H 4
2 O 2
The reaction is balanced
2.- Convert mass of CaC₂ to moles
molecular mass CaC₂ = 40 + (2 x 12)
= 40 + 24
= 64 g
64 g of CaC₂ ----------------- 1 mol
10 g ----------------- x
x = (10 x 1) / 64
x = 10/64
x = 0.16 moles of CaC₂
3.- Calculate the moles of water
1 mol of CaC₂ ----------------- 2 moles of water
0.16 moles of CaC₂ --------- x
x = (0.16 x 2) / 1
x = 0.32 moles of water
Answer:
Answers provided for the reactions with explanations in parenthesis
Explanation:
We need to find the approx. equivalent pH so we can choose an indicator.
CH3COONa +strong acid HCl - methyl orange (pH will be about 4.5)
Na2CO3 base ---> strong acid HCl- phenolphthalein (pH will be 7-8) , and then methyl orange (since carbonic acid has 2 equivalence points, it needs two indicators)
Na2C2O4 HCl- methyl orange, and then methyl orange (since oxalic acid has 2 equivalence points, it needs two indicators)
NH4Cl NaOH- Phenolphthalein, since pH = 9.75 approximately
NaOH HCl-Bromothymol blue --> since pH = 7 best for a neutral indicator
Answer:
1.23 × 10³ N
Explanation:
Step 1: Given and required data
- Mass of the person (m): 125 kg
- Acceleration due to the gravitational force (g): 9.81 m/s²
Step 2: Calculate the force acting between the Earth and a 125-kg person standing on the surface of the Earth
We will use Newton's second law of motion.
F = m × g
F = 125 kg × 9.81 m/s²
F = 1.23 × 10³ N
Answer:
0.19M
Explanation:
2A → A2
Rate constant = 0.0265 M–1min–1
Initial concentration = 2.00 M
Final Concentration = ?
time, t = 180min
The formular relating the parameters is given as;
1 / [A] = kt + 1 / [A]o
1 / [A] = 0.0265 * 180 + (1 / 2)
1 / [A] = 4.77 + 0.5
[A] = 1 / 5.27 = 0.19M