1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Lostsunrise [7]
3 years ago
5

Alexis was interested in the way mirrors reflect. The living room of Alexis' house had one big window in the front, and a very l

arge mirror on the back wall. Alexis hypothesized that the room would heat up faster in the morning with the mirror on the wall than it would if the mirror were covered with a sheet that was the same color as the walls.
What will make Alexis' hypothesis valuable?

a It cannot be valuable because the investigation is in her house and not in the science lab.
b Any testable hypothesis is valuable.
c It will be valuable only if it is proved incorrect.
d It will be valuable only if it is proved correct.
Chemistry
2 answers:
MrRissso [65]3 years ago
8 0

Answer:

Any testable hypothesis is valuable.

Explanation:

Phoenix [80]3 years ago
7 0
It will only be valuable if proved correct so it's D
You might be interested in
Use the standard reaction enthalpies given below to determine ΔH°rxn for the following reaction:P4(g) + 10 Cl2(g) → 4PCl5(s) ΔH°
miskamm [114]

<u>Answer:</u> The \Delta H^o_{rxn} for the reaction is -1835 kJ.

<u>Explanation:</u>

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The given chemical reaction follows:

P_4(g)+10Cl_2(g)\rightarrow 4PCl_5(s)      \Delta H^o_{rxn}=?

The intermediate balanced chemical reaction are:

(1) PCl_5(s)\rightarrow PCl_3(g)+Cl_2(g)    \Delta H_1=157kJ   ( × 4)

(2) P_4(g)+6Cl_2(g)\rightarrow 4PCl_3(g)     \Delta H_2=-1207kJ

The expression for enthalpy of the reaction follows:

\Delta H^o_{rxn}=[4\times (-\Delta H_1)]+[1\times \Delta H_2]

Putting values in above equation, we get:

\Delta H^o_{rxn}=[(4\times (-157))+(1\times (-1207))=-1835kJ

Hence, the \Delta H^o_{rxn} for the reaction is -1835 kJ.

6 0
3 years ago
How is rubidium used
Virty [35]

Answer:

Rubidium is used in vacuum tubes as a getter, a material that combines with and removes trace gases from vacuum tubes. It is also used in the manufacture of photocells and in special glasses. Since it is easily ionized, it might be used as a propellant in ion engines on spacecraft.

Symbol: Rb (37)

Atomic Weight: 85.4678

Atomic Number: 37

Number of Stable Isotopes: 1 (View all isotope .

6 0
3 years ago
(BRAINLIEST) Coal burning plants produce less air pollution than nuclear power plants
Alecsey [184]

Answer:

the answer of this question is true

7 0
3 years ago
Help!!! I need ur help! If u help me I’m going to be so happy. The question is so tricky for me and I don’t know it. If u help m
Mekhanik [1.2K]

I take that the insects remain constant no matter what happens to the frogs (which the frogs eat presumably). So a constant food supply for the frogs is not the problem.

The line for the alligators increases over time. It their numbers increase, the frogs are in trouble. The alligators will pursue lunch with determined single mindedness and there are more of them around.

So the frogs should decrease. Their natural enemy is the alligator and alligators won't go after insects. It's not worth their time.

A is the only answer you can choose.

8 0
3 years ago
weather balloon is filled with helium to a volume of 340 L at 30 ∘C and 751 mmHg . The balloon ascends to an altitude where the
valentinak56 [21]

Answer: Thus the volume of the balloon at this altitude is 419 L

Explanation:

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}

where,

P_1 = initial pressure of gas = 751 mm Hg

P_2 = final pressure of gas = 495 mm Hg

V_1 = initial volume of gas = 340 L

V_2 = final volume of gas = ?

T_1 = initial temperature of gas = 30^oC=273+30=303K

T_2 = final temperature of gas = -27^oC=273-27=246K

Now put all the given values in the above equation, we get:

\frac{751\times 340}{303}=\frac{495\times V_2}{246}

V_2=419L

Thus the volume of the balloon at this altitude is 419 L

8 0
3 years ago
Other questions:
  • Which is not a characteristic of true solutions? 1. exists in only a single phase 2. homogeneous 3. passes through a filter 4. s
    9·2 answers
  • Do you know any of the answers
    7·1 answer
  • How do you balance this chemical equation?
    12·1 answer
  • A product advertised on television claims it can "erase skin blemishes and wrinkles in 90 days or your money back." The best way
    9·2 answers
  • How many grams of silver nitrate are needed to react with 156.2g of sodium sulfide to produce 595.8g of silver sulfide and 340.0
    8·1 answer
  • Match the salt with the acid and base used to form it in a neutralizing reaction. K2SO4
    8·2 answers
  • Find the grams in 1.26*10^-4 mol of HC2H3O2
    15·1 answer
  • If you have 1kg of carbon and 1 kg of gold, they will weigh the same.
    5·1 answer
  • Suppose the reduction of nitric oxide proceeds by the following mechanism:
    5·1 answer
  • 7. The picture below shows a girl with a widow's peak. Widow's peak She has a widow's peak because of her -​
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!