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
Mice21 [21]
3 years ago
7

Min is asked to balance the equation below.

Physics
2 answers:
Minchanka [31]3 years ago
6 0
It is incorrect, because the identity of the original product has changed. Ca3(OH)2 does not exist! It is no longer calcium hydroxide. To balance an equation, you must manipulate the coefficients, a.k.a. the big numbers that go before reactants or products. Subscripts, the little numbers inside the reactants or products, cannot be changed without completely changing the substance.
Wewaii [24]3 years ago
6 0

Ca3P2 + H2O → Ca(OH)2 + PH3

Min’s result: Ca3P2 + H2O → Ca3(OH)2 + PH3

Which best describes Min’s method for balancing the chemical equation?

It is correct, because now there are three Ca atoms on each side of the equation.

It is incorrect, because the identity of the original product has changed.

It is correct, because Ca3(OH)2 creates a more stable compound.

It is incorrect, because the subscript “2” should be added instead.

Answer: B

You might be interested in
_ is where there are no particles or very few particles that are spaced out very far apart. (example: outer space)
irina1246 [14]
The answer is d - Vacuum
4 0
2 years ago
.A coin rolls off the edge of a table. The coin
geniusboy [140]

Answer:

Apply the following formulae horizontally And get A value for time

Remember horizontal acceleration is zero

s  = ut +  \frac{1}{2}a {t}^{2}   \\ 0.8 = 1.7 \times t \\  \frac{0.8}{1.7}  = t \\ t = 0.47s

and then to find the height apply the same above equation vertically...remember vertical initial velocity is zero

s = ut +  \frac{1}{2} a {t}^{2}  \\ s =  \frac{1}{2}  \times 10 \times (0.47) ^{2}  \\ s = 1.1045m

5 0
2 years ago
An offshore oil well is 2 kilometers off the coast. The refinery is 4 kilometers down the coast. Laying pipe in the ocean is twi
shusha [124]

Answer:

Rectangular path

Solution:

As per the question:

Length, a = 4 km

Height, h = 2 km

In order to minimize the cost let us denote the side of the square bottom be 'a'

Thus the area of the bottom of the square, A = a^{2}

Let the height of the bin be 'h'

Therefore the total area, A_{t} = 4ah

The cost is:

C = 2sh

Volume of the box, V = a^{2}h = 4^{2}\times 2 = 128            (1)

Total cost, C_{t} = 2a^{2} + 2ah            (2)

From eqn (1):

h = \frac{128}{a^{2}}

Using the above value in eqn (1):

C(a) = 2a^{2} + 2a\frac{128}{a^{2}} = 2a^{2} + \frac{256}{a}

C(a) = 2a^{2} + \frac{256}{a}

Differentiating the above eqn w.r.t 'a':

C'(a) = 4a - \frac{256}{a^{2}} = \frac{4a^{3} - 256}{a^{2}}

For the required solution equating the above eqn to zero:

\frac{4a^{3} - 256}{a^{2}} = 0

\frac{4a^{3} - 256}{a^{2}} = 0

a = 4

Also

h = \frac{128}{4^{2}} = 8

The path in order to minimize the cost must be a rectangle.

8 0
3 years ago
The pulley system below uses a gasoline engine to raise a drill head up through a smooth drill pipe. The engine provides a const
polet [3.4K]

NB: The diagram of the pulley system is not shown but the information provided is sufficient to answer the question

Answer:

Power = 2702.56 W

Explanation:

Let the power consumed be P

Energy expended = E = mgh

height, h = 5 m

E = 80 * 9.8 * 5

E = 3920 J

Power = \frac{Energy}{time}

To calculate the time, t

From F = ma

F = 900 N

900 = 80 a

a = 900/80

a = 11.25 m/s²

From the equation of motion, s = ut + 0.5at^{2}

The drill head starts from rest, u = 0 m/s

5 = 0 * t + (0.5*11.25*t^{2} )\\5 = 5.625t^{2}\\t^{2} = 5/5.625\\t^{2} = 0.889\\t = 0.943 s

Power, P = E/t

P = 3920/0.0.943

P = 4157.79 W

But Efficiency, E = 0.65

P = 0.65 * 4157.79

Power = 2702.56 W

6 0
3 years ago
The scientific method _____.
Lubov Fominskaja [6]
The answer is D I took the test
3 0
3 years ago
Other questions:
  • Two manned satellites approaching one another at a relative speed of 0.450 m/s intend to dock. The first has a mass of 4.50 ✕ 10
    10·1 answer
  • Which biom ha hot days, cool nights, and very few plants
    14·1 answer
  • What type of energy is produced when friction acts
    14·1 answer
  • What determines the amount of current which will flow through a battery while it is being charged by a constant voltage source?
    14·1 answer
  • How is Oil bad for the environment?
    7·2 answers
  • arlene is to walk across a high wire strung horizontally between two buildings 10.0m apart. The sag in the rope when she is at t
    10·2 answers
  • You pull the plunger back on a pinball machine. The spring is pulled back 25 cm from its rest position and has a spring constant
    15·1 answer
  • n the lab, you performed a trial where the fan was turned off partway through the run. What did the graph for this trial look li
    14·1 answer
  • Under conditions of conservation of energy where the initial energy object is only gravitiational potential energy and the final
    9·1 answer
  • 11. Find the direction of the Force
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!