Answer:
B) -4.1 units
Explanation:
According to this question, a state property X has a value 89.6 units. It undergoes the certain changes as follows:
- first increase by 3.6 units
- then increase by another 18.7 units
- then decrease by 12.2 units
- and finally attains a value of 85.5 units
This can be mathematically represented by 89.6 - {3.6 + 18.7 - 12.2 - x) = 85.5
To get x, we say;
89.6 + 3.6 = 93.2
93.2 + 18.7 = 111.9
111.9 - 12.2 = 99.7
99.7 - 85.5 = 14.2units.
The changes that occured is represented as follows:
= (3.6 + 18.7) - (12.2 + 14.2)
= 22.3 - 26.4
= -4.1 units
Which of the following most likely happens when thermal energy is removed from a chemical reaction?
Answer:
fewer collisions occur between particles or lowering the temperature
Explanation:
2. Al(OH),(s) + 3 HCl(aq) à 3 H2O(l) + AlCl3(aq). This reaction shows how aluminum hydroxide
in antacid tablets neutralizes hydrochloric acid in the stomach. A tablet containing 0.25 g of
aluminum hydroxide is ingested by a patient with 0.88 g of hydrochloric acid in their stomach. Is
this tablet sufficient to neutralize the acid in the patient's stomach? Explain using stoichiometric
calculations. [4 marks]
I
This tablet insufficient to neutralize the acid in the patient's stomach
Further explanationReaction
Al(OH)₃(s) + 3HCl(aq) ⇒ 3 H₂O(l) + AlCl₃(aq)
0.25 g of Aluminum hydroxide-Al(OH)₃ , mol (MW=78 g/mol) :
[tex]\tt \dfrac{0.25}{78}=0.00321[/tex]
mol HCl : mol Al(OH)₃ = 3 : 1
[tex]\tt mol~HCl=3\times 0.00321=0.00963[/tex]
mass HCl (MW=36,46 g/mol) :
[tex]\tt 0.00963\times 36.46=0.351[/tex]
0.351 < 0.88⇒this tablet insufficient to neutralize the acid
I need some help with this
Which of the following is an indication of a physical change?
O A. The formation of a new substance
O B. Giving off a smell
O C. A change in the shape of a substance
O D. The production of gas and heat
Answer:
A change in the shape of a substance
Explanation:
Because when ths shape of a sunstance changes , its physical appearance changes .A physical change is a change to the physical—as opposed to chemical—properties of a substance. They are usually reversible. The physical properties of a substance include such characteristics as shape (volume and size), color, texture, flexibility, density, and mass.
You are doing math homework and get frustrated and throw the 7 kg book with a force of 47
Newtons. How much acceleration will the book have when you throw it?
Answer:
The answer is 6.71 m/s²Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
[tex]a = \frac{f}{m} \\ [/tex]
f is the force
m is the mass
From the question we have
[tex]a = \frac{47}{7} \\ = 6.714285...[/tex]
We have the final answer as
6.71 m/s²Hope this helps you
How is the process of photosynthesis essential to sustaining life on Earth?
Answer:
Explanation:
Photosynthesis is important to living organisms because it is the number one source of oxygen in the atmosphere. Without photosynthesis, the carbon cycle could not occur, oxygen-requiring life would not survive and plants would die. ... The importance of photosynthesis in our life is the oxygen it produces
Use your answers from questions 1–3 as the basis for the first section of your lab report. This section provides your reader with background information about why you conducted this experiment and how it was completed. Outline the steps of the procedure in full sentences. It also provides potential answers (your hypothesis/es) relative to what you expected the experiment to demonstrate. This section should be 1–3 paragraphs in length.
Answer:
1-state what the lab is about, that is, what scientific concept (theory, principle, procedure, etc.) you are supposed to be learning about by doing the lab. You should do this briefly, in a sentence or two. If you are having trouble writing the opening sentence of the report, you can try something like: "This laboratory experiment focuses on X…"; "This lab is designed to help students learn about, observe, or investigate, X…." Or begin with a definition of the scientific concept: "X is a theory that…." 2-give the necessary background for the scientific concept by telling what you know about it (the main references you can use are the lab manual, the textbook, lecture notes, and other sources recommended by the lab manual or lab instructor; in more advanced labs you may also be expected to cite the findings of previous scientific studies related to the lab). In relatively simple labs you can do this in a paragraph following the initial statement of the learning context. But in more complex labs, the background may require more paragraphs.
Explanation:
Answer: the correct answer is A
Explanation:
Help please! A gas occupies 500 mL at 270 mm Hg and 55°C. If the pressure is changed to 1.8 atm and the temperature is
increased to 100°C, what is the new volume? Be sure to show the setup and the final answer and unit.
Show Your Work
Answer:
V₂ = 112.14 mL
Explanation:
Given data:
Initial volume = 500 mL
Initial pressure = 270 mmHg (270/760 =0.355 atm)
Initial temperature = 55 °C (55 +273 = 328 K)
Final temperature = 100°C (100+273 = 373 K)
Final volume = ?
Final pressure = 1.8 atm
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 0.355 atm × 500mL × 373 K / 328 K × 1.8 atm
V₂ = 66207.5 atm .mL. K / 590.4 K.atm
V₂ = 112.14 mL
Which of these ions has the correct charge?
O2-
B2+
P2-
Li2+
Answer:
02- i think your welcome hope it helps
We can change the substance chemically by
freezing it.
True or false
how to know the unknown metal in flame test
Explanation:
The flame test is used to visually determine the identity of an unknown metal or metalloid ion based on the characteristic color the salt turns the flame of a Bunsen burner. The heat of the flame excites the electrons of the metals ions, causing them to emit visible light
please help I need to ace this test
When two atoms attach to each other by sharing electrons it is called a...
A: Covalent bond
B: Ionic bond
C: none of these - atoms can't bond to each other.
D: Nuclear bond
2nd question
Two hydrogen atoms bonded together form a compound
A: True
B: False
3rd question
Water is two hydrogen atoms bonded to an oxygen atom. This is an example of a compound
A: True
B: False
like I said I need help on this and I don't wanna fail
#1: A covalent bond
#2 False
#3True
Air that has been removed from a bell jar will NOT allow _____________ waves to travel through the jar. Question 4 options: sound light water
Answer:
Sound.
Explanation:
Sound requires a medium such as air to travel.
Which best explains why aluminum is a nonrenewable resource?
A)It cannot be quickly replaced.
B)It is expensive to process.
C)It conducts electricity.
D)It is useful to humans.
Answer:
A.) It cannot be quickly replaced.
Explanation:
Aluminum is extremely useful to humans but is semi-difficult to produce. Because of this, your answer will be numero uno. (Or A.)
2. How can glass be a liquid if it's so hard?
Explanation:
Glass is not a liquid in the strictest sense of the word. But it is also not a standard solid. The chemistry of glass is complex and research is ongoing, but the current consensus is that glass is a phase of matter all its own, known as an "amorphous solid". Scientists refer to any amorphous solid as a "glass". Glass transitions are highly complex and cannot be treated in the same way as traditional phase transitions.
Answer:
It's a liquid state before its cooled.
if the atomic mass is 14 and the atomic number is 7,how many neutrons do you have?
Answer: 7 neutrons
Explanation: Atomic number refers to the number of protons in the nucleus of the atom. Also you can treat atomic mass as how many particles (protons and neutrons) are in the nucleus of the atom. So for this problem:
14 particles - 7 protons = 7 neutrons (and we know all that's left over is neutrons because we subtracted all the protons)
What is the total number of grams of a 32-gram sample of 32P remaining after 71.5 days of decay?
Answer:
1 g
Explanation:
The following data were obtained from the question:
Original amount (N₀) = 32 g
Time (t) = 71.5 days
Half-life of phosphorus (t½) = 14.3 days
Amount remaining (N) =?
Next, we shall determine the rate of disintegration. This can be obtained as follow:
Half-life of phosphorus (t½) = 14.3 days
Decay constant (K) =?
K = 0.693 / t½
K = 0.693 / 14.3
K = 0.0485 /day
Finally, we shall determine the amount remaining as illustrated below:
Original amount (N₀) = 32 g
Time (t) = 71.5 days
Decay constant (K) = 0.0485 /day
Amount remaining (N) =?
Log (N₀/N) = Kt/2.303
Log (32/N) = 0.0485 × 71.5 / 2.303
Log (32/N) = 3.46775 / 2.303
Log (32/N) = 1.5058
Take the antilog of 1.5058
32/N = antilog (1.5058)
32/N = 32.05
Cross multiply
32 = N × 32.05
Divide both side by 32.05
N = 32 / 32.05
N = 0.998 ≈ 1 g
Thus, the amount remaining after 71.5 days is approximately 1 g.
The half-life of a radioactive substance refers to the time taken for the substance to Decay to half of its initial size. Hence, the mass of the substance left after 71.5 days is 1 gram.
Initial mass = 32 g Half life = 14.3 daysAfter 14.3 days ;
32 / 2 = 16 gramsAfter 14.3 × 2 = 28.6 days :
16/2 = 8 gramsAfter 14.3 × 3 days = 42.9 days :
8 / 2 = 4 gramsAfter 14.3 × 4 days = 57.2 days :
4 /2 = 2 gramsAfter 14.3 × 5 days = 71.5 days :
2 /2 = 1 gram.Hence, the mass of the sample left after 71.5 days would be 1 gram.
Learn more : https://brainly.com/question/18766174
P and Q are two substances such that the melting point of P and the boiling point of Q are the same. If P is a solid at a certain temperature, what state will Q be in at the same temperature?
Answer:
Explanation:
Firstly, it should be noted that melting and freezing points are the same. Thus, when a substance melts at a certain temperature, it means it can also start freezing/solidifying at that same temperature. That been said, when the substance P is a solid at a certain temperature, the other compound Q will boil at that same temperature and hence will be a gas at that same temperature.
If P is solid, it simply means that Q must still be in the liquid state.
From the question, we can see that, the melting point of P and the boiling point of Q are the same. The melting point of a substance is the temperature at which the solid turns to liquid while the boiling point of a substance is the temperature at which a liquid turns to a gas.
If P is solid, it simply means that Q must still be in the liquid state. It has not yet started boiling since the melting point of P and the boiling point of Q are the same.
Learn more: https://brainly.com/question/8553652
Can someone help? Ill give brainliest!
Directions: count each side of the reaction then Circle yes or no if it follows the law of conservation of mass
Answer:
Explanation:
before the reaction you have K=2 and Cl=4
after the reaction K=2 and Cl=2 so it does not follow the law of conservation
When 0.25 moles of NH3 are produced according to the reaction below, how many moles of H2 must have reacted?
N2 + 3 H2 --> 2 NH3
O 1.5 moles H2
O 0.38 moles H2
O 0.25 moles H2
O 0.17 moles H2
Answer:
Explanation:
by stoichiometry
nNH3/2=nH2/3
0.25/2=nH2/3
nH2=0.25×3/2
nH2=0.375 mol
so its 0.38 mol
Answer:
I have this quiz rn I will try 0.38 if it is right I’ll edit this and say that
Explanation:
There are several different models that represent compounds. One type of model is shown.
3 C's connected in a line by 2 black lines. The first and third C's each have 3 H's connected to them by a single black line each. The middle C has 2 H's connected to it by a single black line each.
What type of model is shown?
A) structural formula
On edge
Answer:
A
Explanation:
Which screw would create a strong hold?
A: The screw with 9 wraps.
B: The screw with 2 wraps.
C: The screw with 10 wraps.
D: The screw with 6 wraps.
Answer:
The screw with 10 wraps is the correct answer
Explanation:
The screw with 6 wraps would create a strong hold.
What do you mean by screw?The strongest member of the family of wood screws is a lag screw. It is a reliable and sturdy fastener that frequently has a square head or an externally powered hex drive.
In general, lag screws are significantly stronger and heavier than standard wood screws. They have a tapered point and coarse threads.
Thus, The screw with 6 wraps would create a strong hold.
To learn more about Screw, refer to the below link:
https://brainly.com/question/24168324
# SPJ5
An independent variable is....
A: What we measure
B: What we change
C: What stays the same
D: What we conclude
Answer:
B - What we change
Explanation:
Dependent Variable - What we measure
Control Variable - what stays the same
Conclusion - what we conclude
Hope this can Help!
:D
Identify a metal from the following
(1) Sulphur
(2) Boron
(3) Silicon
(4) Sodium
Answer:
sodium
Explanation:
it is an alkali metal
How many moles of Cl2 are needed in order to produce 100.0 grams of FeCl3 given the following
equation: 2 Fe + 3 Cl2 → 2 FeCl3
B
T
Answer:
0.92moles
Explanation:
Given reaction:
2Fe + 3Cl₂ → 2FeCl₃
Mass of FeCl₃ = 100g
Unknown:
Number of moles of Cl₂ needed = ?
Solution:
To solve this problem, we work from the known specie to the unknown.
From the mass of the FeCl₃ given, we can solve for the number of moles of the unknown.
Number of moles of FeCl₃;Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of FeCl₃ = 56 + 3(35.5) = 162.5g/mol
Number of moles = [tex]\frac{100}{162.5}[/tex] = 0.62mole
From the reaction expression;
2 mole of FeCl₃ is produced from 3 moles of Cl₂
0.62 mole of FeCl₃ will be produced from [tex]\frac{0.62 x 3}{2}[/tex] = 0.92mole
The number of moles of Cl₂ = 0.92moles
A neutral atom contains 12 neutrons and 11 electrons. The number of protons in this atom is
(1) 1 (3) 12
(2) 11 (4) 23
Answer:
1
Explanation:
if a star were 36 trillion miles from the earth it would be about ___ light years from the earth
Answer:
6.12light years
Explanation:
Given parameters:
Distance of star from earth = 36 trillion miles
Unknown:
Distance in light years = ?
Solution:
A light year is the distance light travels in one year.
1 mile = 1.7 x 10⁻¹³ light years
36 trillion miles = 36 x 10¹² x 1.7 x 10⁻¹³ light years
= 6.12light years
What product(s) are formed during this chemical reaction? (Will be two answers)
B(NO3)3 + KBr rightwards arrow
K(Br)3
KNO3
Br3(NO3)2
K3NO4
B(NO3)K
B3K3
BBr3
BK
Answer:
BK. BK. BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK BK
What’s the answer????
Answer:
Greater
Greater
Explanation:
The amplitude of a wave is the height of the wave or the vertical displacement of the wave motion. We determine a wave amplitude usually by looking at the graph of the wave.
Amplitude is directly proportional to the energy of a wave. The higher the amplitude of a wave, the more its energy.
Frequency is the number of waves that passes a point at a particular instance of time. It is also directly proportional to the energy carried by a wave. The higher the frequency of a wave, the greater its energy.
Help me with homework.
The chemical equation is said to be balanced if the number of atoms in the reactants and products is the same
Further explanationEquation balanced ⇒ total number of atoms in reactants(on the left)= total number of atoms in products(on the right)
H₂+O₂---> H₂O
Reactants : H₂, O₂
Products : H₂O
not balanced
H₂O₂ ---> H₂O+O₂
Reactants : H₂O₂
Products : H₂O, O₂
not balanced
Na+O₂ ---> Na₂O
Reactants : Na, O₂
Products : Na₂O
not balanced
N₂+H₂ ---> NH₃
Reactants : N₂, H₂
Products : NH₃
not balanced
P₄+O₂---> P₄O₁₀
Reactants : P₄, O₂
Products : P₄O₁₀
not balanced
Fe+H₂O ----> Fe₃O₄ + H₂
Reactants : Fe, H₂O
Products : Fe₃O₄
not balanced