Please helppppppp. I need this D:<br><br> 50 points

The planet Mercury takes 176 days to do one spin around its pole. Compared to the Earth,

Tanya [424]

Answer:

The sun would appear to move more slowly across Mercury's sky.

Explanation:

This is because, the time it takes to do one spin or revolution on Mercury is 176 days (which is its period), whereas, the time it takes to do one spin or revolution on the Earth is 1 day.

Since the angular speed ω = 2π/T where T = period

So on Mercury, T' = 176days = 176 days × 24 hr/day × 60 min/hr × 60 s/min = ‭15,206,400‬ s

So, ω' = 2π/T'

= 2π/15,206,400‬ s

= 4.132 × 10⁻⁷ rad/s

So on Earth, T" = 1 day = 1 day × 24 hr/day × 60 min/hr × 60 s/min = ‭‭86,400‬ s

So, ω" = 2π/T"

= 2π/86,400‬ s

= 7.272 × 10⁻⁵ rad/s

Since ω' = 4.132 × 10⁻⁷ rad/s << ω" = 7.272 × 10⁻⁵ rad/s, <u>the sun would appear to move more slowly across Mercury's sky.</u>

4 0

2 years ago

In the laboratory, hydrogen gas is usually made by the following reaction: Zn(s) + 2 HCl(aq) → H2(g) + ZnCl2(aq) How many liters

IrinaK [193]

<u>Answer:</u> The volume of hydrogen gas collected over water is 2.13 L

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of zinc = 5.566 g

Molar mass of zinc = 65.4 g/mol

Putting values in above equation, we get:

$\text{Moles of zinc}=\frac{5.566g}{65.4g/mol}=0.0851mol$

For the given chemical reaction:

$Zn(s)+2HCl(aq.)\rightarrow H_2(g)+ZnCl_2(aq.)$

As, HCl is present in excess. So, it is considered as an excess reagent.

Zinc is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

1 mole of zinc produces 1 mole of hydrogen gas.

So, 0.0851 moles of zinc will produce = $\frac{1}[1}\times 0.0851=0.0851mol$ of hydrogen gas

To calculate the volume of hydrogen gas, we use ideal gas equation, which is:

PV = nRT

where,

P = Pressure of hydrogen gas = Total atmospheric pressure - vapor pressure of water = (752 - 18.65) mmHg = 733.35 mmHg

V = Volume of the hydrogen gas

n = number of moles of gas = 0.0851 moles

R = Gas constant = $62.3637\text{ L.mmHg }mol^{-1}K^{-1}$

T = Temperature of hydrogen gas = $21^oC=[21+273]K=294K$

Putting values in above equation, we get:

$733.35mmHg\times V=0.0851mol\times 62.3637\text{ L.mmHg }mol^{-1}K^{-1}\times 294K\\\\V=\frac{0.0851\times 62.3637\times 294}{733.35}=2.13L$

Hence, the volume of hydrogen gas collected over water is 2.13 L

5 0

3 years ago

Please help!!!!

stealth61 [152]

Answer:

Cells are extremely small.

Explanation:

As Mendel describes in this story, cells are so small they cannot normally be seen with the naked eye. ... The total organism remains the same throughout this process, and (usually) has a longer time on earth than any one of its cells.

3 0

2 years ago

2C2H2(g)+5O2(g)=4CO2(g)+2H2O(g)

balandron [24]

The volume of ethyne, C₂H₂ required to produce 12 moles of CO₂ assuming the reaction is at STP is 134.4 L

<h3>Balanced equation</h3>

2C₂H₂(g) + 5O₂(g) --> 4CO₂(g) + 2H₂O(g)

From the balanced equation above,

4 moles of CO₂ were produced by 2 moles of C₂H₂

<h3>How to determine the mole of C₂H₂ needed to produce 12 moles of CO₂</h3>

From the balanced equation above,

4 moles of CO₂ were produced by 2 moles of C₂H₂

Therefore,

12 moles of CO₂ will be produce by = (12 × 2) / 4 = 6 moles of C₂H₂

<h3>How to determine the volume (in L) of C₂H₂ needed at STP</h3>

At standard temperature and pressure (STP),

1 mole of C₂H₂ = 22.4 L

Therefore,

6 moles of C₂H₂ = 6 × 22.4

6 moles of C₂H₂ = 134.4 L

Thus, we can conclude that the volume of C₂H₂ needed for the reaction at STP is 134.4 L

Learn more about stoichiometry:

brainly.com/question/14735801

#SPJ1

3 0

2 years ago

How many liters of H2O gas are produced when

anyanavicka [17]

1 mole C3H8 produces 4 moles H2O. So, first we convert 32 grams of propane to moles and then find moles of H2O. Then convert moles of H2O to grams of H2O
Moles of H2O produced = 32 g C3H8 x 1 mole/44 g x 4 moles H2O/mole C3H8 = 2.909 moles H2O
Grams H2O produced = 2.909 moles H2O x 18 g/mole = 52.36 g = 52 g H2O

8 0

2 years ago

Please helppppppp. I need this D: 50 points