Chemistry, 10.03.2020 11:04 andrejr0330jr
The accepted ΔH for a reaction is −42.3 kJ/mol. A student has performed a lab experiment to determine the enthalpy change of the same reaction. Calculate the percent error
Student 1 Exp. ΔH(kJ/mol)
Trial 1 –43.8
Trial 2 –41.0
Trial 3 –42.7
Answers: 2
Chemistry, 21.06.2019 17:30
How many grams of magnesium metal will react completely with 8.3 liters of 5.5 m hcl? show all of the work needed to solve this problem. mg (s) + 2hcl (aq) → mgcl2 (aq) + h2 (g)
Answers: 3
Chemistry, 21.06.2019 22:30
Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial
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Chemistry, 22.06.2019 08:00
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Answers: 1
Chemistry, 22.06.2019 11:20
Which of the following contributes to the structural rigidity of cellulose? adjacent glucose polymers are stabilized by hydrogen bonding. glucose residues are joined by (α1→4) linkages. cellulose is a highly branched molecule. the conformation of the glucose polymer is a coiled structure.
Answers: 2
The accepted ΔH for a reaction is −42.3 kJ/mol. A student has performed a lab experiment to determin...
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