Answer:
C. A physical change.
Explanation:
A liquid is cooled during an investigation causing it solidify.Which of the following most likely occurred?
A. Absorption of heat. NO. Heat was released.
B. A chemical change. NO. It was a physical change
C. A physical change. YES. The physical change is called solidification.
D. Formation of a new compound. NO. This would be a chemical change.
Which of the following is NOT a
homogenous mixture?
Answer:blacks screen. No answers to choose from. Thanks for the points:))
Explanation:
A mixture of propane and butane is burned with pure oxygen. The combustion products contain 46.7 mole% H2O. After all the water is removed from the products, the residual gas contains 69.0 mole% CO2 and the balance O2 a. What is the mole percent of propane in the fuel?
Answer:
28%
Explanation:
Basically, all o did was write the equations, balance it and solve for them. Also, at the place I stared, I used simultaneous equation to solve it. Multiplying by 8 and also 3.
It's a pretty straightforward question.
At the final step that's missing, I Did
(y)C3H8 = 2.8 / ( 2.8 + 7.1)
(y)C3H8 = 0.28
What is the pH after two solutions are mixed: 1. A 0.155 M H2SO4 solution with a volume of 35.0 mL and 2. A 0.225 M solution of KOH with a volume of 35.0 mL. The volumes are additive.
Answer:
[tex]pH=1.67[/tex]
Explanation:
Hello.
In this case, since the reaction between the sulfuric acid and the potassium hydroxide is:
[tex]2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O[/tex]
We can see a 2:1 mole ratio between them, thus, we compute the moles of acid and base that are present in the solution by using the employed volume and its concentration:
[tex]n_{H_2SO_4}=0.155mol/L*0.0350L=0.005425molH_2SO_4\\\\n_{KOH}=0.225mol/L*0.0350L=0.007875molKOH\\[/tex]
Next, we use the 2:1 mole ratio to compute the consumed moles of acid:
[tex]n_{H_2SO_4}^{consumed}=0.007875molKOH*\frac{1molH_2SO_4}{2molKOH}=0.0039375molH_2SO_4[/tex]
It means that the leftover of sulfuric acid is:
[tex]n_{H_2SO_4}^{leftover}=0.005425-0.0039375=0.001488molH_2SO_4[/tex]
Therefore, since sulfuric acid is a strong acid, the pH is defined in terms of its concentration which is actually equal to the concentration of hydrogen ions in solution, which is computed considering the total additive volume:
[tex][H^+]=[H_2SO_4]=\frac{0.001488mol}{0.070L}=0.02125M[/tex]
So the pH turns out:
[tex]pH=-log(0.02125)\\\\pH=1.67[/tex]
Best regards.
Complete the sentence by using "Direct", "Inverse", or equal. The pressure and volume of a gas change in opposite directions. This can be described as an " upside-down" relationship. We can also say that the relationship between the pressure and volume of a gas is a __________________ relationship
answer:
i believe the answer is inverse.
if i'm wrong sorry :(
if i'm right your welcome :)
((50 BRAINLY POINTS))
Guys I really need your help on this! It's timed!
Answer:
its only 25
Explanation:
lab
table b:eyedrop of blue water in cold water
table c:eyedrop of red water in hot water
table d:see how temperature changes on white + black paper with light shining on them
plz help
brainliest for 1st correct answer
Answer:
lol, I just did this assignment, cold water
0:30: slowly expand
1:00: still expanding
1:30: expanding is continued
2:00: still expanding slowly
2:30: expanding slowly
3:00: expanded twice the size from the first time
hot water
0:30: expanding quickly
1:00: still expanding
1:30: starts to reach the surface and still expanding
2:00: almost all the of the dye reached the top
2:30: the dye reached the top and is starting to split
3:00: the dye split appart and is moving down again
radiation
white paper
0:30: at a low temp. at around 3.3 C
1:00: still at a low temp. around 4.4 C
1:30: slowly rising temp. around 5.5 C
2:00: still slowly rising temp. around 7.2 C
2:30: still at a low temp. around 8.3 C
3:00: ends at a low temp. around 10 C
black paper
0:30: at a resonable temp. at around 6.6 C
1:00: temp. rises quicker at around 13.3 C
1:30: temp. stil rising quickly at around 17.7 C
2:00: temp. is getting hotter at around 21.6 C
2:30: temp. is still getting hotter at around 26.1 C
3:00: temp. ends at a hot temp. at around 30 C
Explanation:
What functional group results when cyclopentanone reacts with ethylamine in the presence of trace acid? A) cyanohydrin B) semicarbazone C) imine D) enamine E) oxime
Why do we need to identify matter?
Answer:
It's important for scientists to know the properties of matter because all things are made up of matter. Each type of matter has different physical characteristics and scientists need to know and understand these characteristics to make calculations. ... The main phases of matter are solid, liquid, and gas
Explanation:
^^
C. If an electron is added to the outer shell, how will this affect the charge and volume of the atom?
if an electron is added on the outer shell
Answer:
An atom that gains or loses an electron becomes an ion. If it gains a negative electron, it becomes a negative ion. If it loses an electron it becomes a positive ion.
Answer:
when an atom gains an electron, it gains a negative charge . it's volume increases as well due to the increase in repulsion between the electrons
According to the nissani what can be some possible ways to save the forest of third world countries
Answer:
This question is incomplete
Explanation:
This question is incomplete. However, there are ways to save the forest of third world countries - this includes
1) Creating of forest reserves: Wide areas of land that are still forested can still be preserved and converted to forest reserves which can prevent these areas from being deforested as a result of human activities or industrialization.
2) Government policies: Government can put policies in place to prevent people from embarking on deforestation of certain lands. This is because some parts of the third world countries still rely on wood for cooking and other sources of daily activities.
3) Replanting of deforested areas: Replanting of trees can also help third world countries in saving the forest.
An element that has an electronegativity value of zero
Answer:
Noble gases
Explanation:
Noble gases
True or false, physical properties are distinguished by the way something looks, taste, smell, and feels.
Answer:
True
Explanation:
Physical properties are based on all of our five senses, so yeah
Which of the following are membranous sacs abundant in kidney and liver cells?
a. golgi bodies
b. mitochondria
c. lysosomes
d. peroxisomes
Answer: it’s B!! :)