Answer:
Holly observes that the ice pack becomes colder when she activates it.
Explanation:
She infers that the process of the urea dissolving in water is endothermic.
Answer:
The correct answer is option 4.
The complete balanced chemical reaction for this is:
C6H8O7 + 3 NaHCO3 ---> 3 H2O + 3 CO2 + Na3C6H5O7
First calculate for the number of moles of each reactant.
moles C6H8O7 = 1 g / (192.124 g / mol) = 5.2 * 10^-3 mol
moles NaHCO3 = 1 g / (84.01 g / mol) = 11.9 * 10^-3 mol
A. The ratio of the reactant from the chemical reaction
is 3NaHCO3:1C6H8O7, while the given chemicals are in the ratio of:
11.9 * 10^-3NaHCO3: 5.2 * 10^-3 C6H8O7 =
2.29NaHCO3:1C6H8O7
Therefore this means that there is less amount of NaHCO3
supplied than what is required therefore the limiting reactant is:
NaHCO3
B. We calculate based on the limiting reactant.
mass CO2 = 11.9 * 10^-3 mol NaHCO3 (3 mol CO2/1 mol
NaHCO3) (44.01 g/mol)
mass CO2 = 1.57 g
C. I believe what is asked here is the amount of excess
reactant which remains. The excess reactant is C6H8O7.
mass C6H8O7 left = [5.2 * 10^-3 mol – (11.9 * 10^-3 mol
NaHCO3 (1 mol C6H8O7/ 3 mol NaHCO3))] * (192.124 g / mol)
mass C6H8O7 left = 0.237 g
Emission spectrum
Explanation:
The emission spectrum is the characteristic color bands emitted by element when they become excited.
The spectrum denotes the amount energy that each respective atom absorbs.
Emission spectrum is very unique to every element becomes atoms gives off electromagnetic radiations within a range that typifies them.
The color band indicate the amount of energy emitted in form of electromagnetic radiation.
When electrons in an atom gain energy, the become excited, on falling and losing their energy, they return to their ground state releasing the measure of energy they absorbed in transitioning.
learn more:
Electron transition brainly.com/question/4986277
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Answer:
Limiting reactant: Cl2.
Max mass of PCl3 = 41.44 g.
P4 leftover = 5.51 g.
Explanation:
Hello!
In this case, since the undergoing chemical reaction is:
In order to compute the maximum amount of PCl3, it is necessary to compute the grams of this product produced by each reactant, just as shown below, whereas molar masses and mole ratios are used:
Thus, since chlorine gas yields fewer grams of PCl3 than P4 we infer Cl2 is the limiting reactant and 63.41 grams of PCl3 product are yielded.
Finally, for the excess reactant, we see a difference of 63.41-41.44=21.97g, so we can compute of the leftover of P4 as follows:
Best regards!