Answer:
A. 20 grams of milk at 10°C
Explanation:
Since we refrigerate milk, it would be cooler than the room temperature, which standard norm is 25°C. So the milk has to be colder than the room temperature. Therefore, our answer is A.
Answer: A is the correct answer
Explanation:
The temperature of room temperature is more than that and you need to keep it colder, hope this helped!
Which lifestyle is most likely to lead to infertility in a male ?
A man who works as a mechanic
A man who works as a computer programmer and sits at desk magority of the day
A semi professional athlete
A man who works for a company’s that applies pesticides to lawns
Answer:
The second on, A man who works as a computer programmer and sits at desk magority of the day.
Explanation:
Answer:
Explanation:
The only answer I can think as being possible is the last one. Pesticides are chemicals that go after unwanted animal life. They do not know that they should not attack human beings.
Infertility could very well be one of the side effects of a pesticide. There are others as well. Some pesticides go after the central nervous system (think mice and rats) and those are dangerous to use and to leave around.
The others all involve occupations that either require authentic abilities or mental astuteness. Neither should affect a man's ability to reproduce.
1. A 10.0 g sample of propane, C3H8, was combusted in a constant-volume bomb
calorimeter. The total heat capacity of the bomb calorimeter and water was 8.0
kJ/°C. The molar heat of combustion of propane is -2 222 KJ/mol. If the starting
temperature of the water was 20 °C, what will be the final temperature of the
bomb calorimeter?
Answer:
The final temperature of the bomb calorimeter is 82.98°C
Explanation:
The given information are;
The mass of the propane sample = 10.0 g
The heat capacity of the bomb calorimeter = 8.0 kJ/°C
The molar heat of combustion of propane is -2,222 kJ/mol.
The starting (initial) temperature of the water, T₁ = 20°C
The final temperature of the bomb calorimeter = T₂
The molar mas of propane = 44.1 g/mol
The number of moles, n, of propane present in 10.0 g of propane is found as follows;
[tex]Number \ of \ moles \ of \ propane, \ n = \dfrac{Mass \ of \ propane}{Molar mass \ of \ propane} = \dfrac{10}{44.1} = 0.227 \ moles[/tex]Which gives;
The heat, Δh, released from the combustion of 10.0 g of propane = 0.227 × -2222 kJ/mol
Δh = -503.85 kJ/mol
Heat gained by the calorimeter = Heat released from the combustion of 10.0 g of propane = 503.85 kJ/mol
Change in heat, Δh[tex]_c[/tex] in the calorimeter = Heat capacity × Temperature change
Δh[tex]_c[/tex] = m × C
503.85 kJ/mol = 8.0 kJ/°C × (T₂ - 20°C)
T₂ = -503.85 kJ/mol/(8.0 kJ/°C) + 20°C = 82.98°C
The final temperature of the bomb calorimeter = 82.98°C
The correct name for molecule I is
Molecule I
I
|
CH3-CH-CH3
a. Iodopropane
b. 2-iodylpropane
c. 2-iodopropane
D. Propyliodine
14. The correct name for molecule III is
Molecule III
F
|
C= CH
——-
a. 2-Fluoroeth 1-yne
b. Fluoroethyne
C. Fluoroethene
D. Methylfluorine
16. Synthetic chlorinated hydrocarbons such as dioxins and furans are usually greater pollution hazard then natural organic substances because synthetic hydrocarbons are
a. More volatile
b. Less water soluble
C. Less Biodegradable
D. More chemically reactive
Question 17.
Sources of pollutants
1. High temperature combustion
2. Pulp and paper industry
3. Pesticides
4. Sour gas plants
Match each source of pollutant as numbered above with its pollutant as listed below. Use each number only once
17. Dioxins/furans
18. SO2(g)
19. Nox(g)
20. Phosphates
Answer:
c). 2-iodopropane
14) C). Fluoroethene
16) D). More chemically reactive
17) 1). High temperature combustion - Dioxins/furans
2). Pulp and paper industry - SO2(g)
3). Pesticides - Phosphates
4). Sour gas plants - Nox(g)
Explanation:
The correct name for molecule I would be '2-iodopropane' where the number 2 reflects the position of iodine. There are three carbons and 8 hydrogen atoms which reflect that it is an alkane compound. In the given carbon chain. In this chain of three carbons, iodine is present on the second carbon. Therefore, option C is the correct answer.
14). The appropriate name for molecule III exemplifies Fluoroethene as it consists of two carbons due to which it belongs to the 'ethane' group and it bears the prefix 'fluoro as it belongs to fluorine group and the suffix '-ene' due to double bond.
16). Synthetic hydrocarbons are 'more chemically reactive' and therefore, it generates greenhouse gases and leads to climate change, global warming, depletion of the ozone layer, etc.
17). 1). Dioxins are generated as a result of high-temperature combustion processes like commercial waste incineration or burning of fuels.
2). Pulp and paper industry releases various gases like nitrogen oxide, sulfur dioxide SO2(g), carbon dioxide, etc.
3). Phosphate is the pollutant released from pesticides that badly affects the fertility of the soil.
4). Nox(g) nitrogen oxide released by sour gas plants and coal-fired emissions is a major contributor to increased greenhouses gases and global warming.
Sugar can be converted to carbon dioxide and water by burning in air or by metabolic reactions inside living cells. How are these reactions similar and how are they different?
Answer:
These reactions are similar because the process is similar and the products are carbon dioxide they are different because the substances are different to outgo these reactions
Explanation:
2. If the reaction of 5.75 moles of sodium with excess hydrofluoric acid is able to produce 2.49 mol H2, what is the percent yield of hydrogen gas?
Unbalanced equation:
Na + HF –> NaF + H2
94.2%
86.5%
43.3%
23.1%
Answer:
86.5%
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
2Na + 2HF –> 2NaF + H2
Next, we shall determine the theoretical yield of the hydrogen gas, H2. This is illustrated:
From the balanced equation above,
2 moles of Na reacted to produce 1 mole of H2.
Therefore, 5.75 moles of Na will react to produce = (5.75 x 1)/2 = 2.88 moles of H2.
Therefore, the theoretical yield of Hydrogen gas, H2 is 2.88 moles.
Finally, we shall determine the percentage yield of Hydrogen gas, H2. This can be obtained as follow:
Actual yield of H2 = 2.49 moes
Theoretical yield of H2 = 2.88 moles
Percentage yield of H2 =.?
Percentage yield = Actual yield /Theoretical yield x 100
Percentage yield = 2.49/2.88 x 100
Percentage yield = 86.5%
Therefore, the percentage yield of Hydrogen gas, H2 is 86.5%.
procedure to find out if the penny is real copper with copper wire
Answer:
Four ways to test a copper penny are given below:-
Explanation:
Firstly, take a quick look only at the color of the penny. Zinc pennies may appear patchy, irregular whereas copper-gold coins may seem more probable to be orange or even chocolate. Secondly, drop your penny on the floor and hear the noise it's making. The copper penny would have a "started to ring" sound in this situation, whereas the zinc penny should "clunk." Third, you can weigh the centimeter. You'll need an accurate scale weighing in grams. The penny of copper will weigh 3.11 grams while the penny of zinc weighs 2.5 grams. In the end, look at the date. If your penny was taken out of circulation before 1982, 95 percent copper and 5 percent zinc will be made. Beginning in 1982, pennies had just 2.5 percent copper and 97.5 percent zinc in them. Pennies from any of the two formulations made in 1982 may be produced.
What qualifications do you need to be a research scientist?
A. High IQ
B. College degree
C. High school diploma
D. Ph.D
Answer:
Ph.D
Explanation:
For the most part, research scientists need a bachelor's degree in a highly associated field. A master's degree or a doctorate is frequently expected.
Consider preparing ammonia gas by the following reaction:
N2(g) + 3H2(g)
===>
2NH3(g)
If you have 28.02 g of N2 and excess H2, how many grams of NH3(g) can be produced.
6.06 g
14.01 g
34.08 g
68.16 g
28.02 g
Answer:
34.08 g
Explanation:
Take the atomic mass of N=14.0, H=1.0/
no. of moles=mmass/molar mass
no. of moles of N2 used = 28.02 / (14x2)
=1.0007mol
From the equation, the mole ratio of N2 : NH3 = 1: 2,
so one mole of N2 produces 2 moles of NH3.
Using this ratio, we can deduce that the no. of moles of NH3 = 1.0007x2
= 2.001428mol
mass = no. of moles x molar mass
Hence,
mass of NH3 produced = 2.001428 x (14+1x3)
= 34.03
≈C