Response:
9.606 g
Clarification:
Step 1: Write the balanced combustion equation
C₂H₆O(l) + 3 O₂(g) → 2 CO₂(g) + 3 H₂O(g)
Step 2: Determine the moles for 11.27 g of H₂O
The molar mass of H₂O is 18.02 g/mol.
11.27 g × (1 mol/18.02 g) = 0.6254 mol
Step 3: Find the moles of C₂H₆O that produced 0.6254 moles of H₂O
The ratio of C₂H₆O to H₂O is 1:3. Thus, the moles of C₂H₆O are 1/3 × 0.6254 mol = 0.2085 mol
Step 4: Calculate the mass for 0.2085 moles of C₂H₆O
The molar mass of C₂H₆O is 46.07 g/mol.
0.2085 mol × 46.07 g/mol = 9.606 g
A total of 0.0222 moles of NaOH are necessary to react with NH4F. \nBased on the reaction NH4F + NaOH --> NaF + NH3 + H2O, we start with: \nMass of NH4F = 0.821 g, NaOH concentration = 1 M, volume of NaOH = 25 mL. \nTo find moles: moles of NaOH = (CV)/1000. Thus, moles of NaOH = (1 * 25)/1000 = 0.025 moles of NaOH used. \nThe molar mass of NH4F is 37 g/mol, making moles of NH4F = 0.821 / 37 = 0.0222 moles. \nThis shows that NaOH is in excess, with 0.025 - 0.0222 = 0.0028 moles of NaOH remaining. Hence, 0.0222 moles of NaOH are needed to react with NH4F.
Yasir wished to explore how sleep relates to room color. He conducted necessary preliminary research and formed a hypothesis suggesting individuals doze off faster in blue-painted rooms compared to those painted in yellow. Yasir surveyed several individuals about their color preference—yellow or blue—and utilized their feedback to assess the validity of his hypothesis. However, he did not conduct an actual experiment to examine the impact of room color on sleep, and he failed to clearly define the variables that should have been part of his experiment.
Hence, the correct answer would be,
An experiment that directly tests the hypothesis
Variables to be tested by an experiment
Answer:
Please review the following responses
Explanation:
1) A solution of 100. mL contains 19.5 g of NaCl (3.3M)
2) 100. mL of NaCl solution at 3.00 M (3 M)
3) A solution of 150. mL holds 19.5 g of NaCl (2.2 M)
4) The concentrations of beakers 1 and 5 are identical (1.5M)
Molar mass of NaCl = 23 + 36 = 59 g
For beaker number 3:
59 g -------------- 1 mol
19.5 g ------------- x
x = 19.5 x 1/59 = 0.33 mol
Molarity (M) = 0.33 mol/0.150 l = 2.2 M
For beaker number 4:
Molarity (M) = 0.33mol/0.10 l = 3.3 M
For beaker number 5:
Molarity (M) = 0.450/0.3 = 1.5 M
Convert 55.0g Ca(OH)2 to moles.
The calculation shows that 55.0g of Ca(OH)2 corresponds to 0.742 moles.
To find the volume, divide 0.742 mol of Ca(OH)2 by its molarity of 0.680M, yielding approximately 1.09L of Ca(OH)2.
If you disregard the negligible volume of the Ca(OH)2 itself, the resulting total volume of a 0.680M solution created by dissolving 55.0g of Ca(OH)2 in an appropriate amount of water would be 1.09L.
