3. An area where a particular plant has thrived for 50 million years suffers a
100-year-long drought. What evidence of the drought might be found in the fossil
record?
A. Fossils of the plant are abundant right up until the present day.
B. Fossils of the plant appear in recent rock layers but not in older ones.
C. Fossils of the plant are present in older rocks but disappear at a point in the
fossil record
D. It is impossible for the fossil record to show evidence of the drought.

Answer:

2.040 mol CO

Explanation:

First, write out your reaction:

CO + O2 --> CO2

Balance the reaction:

2CO + O2 --> 2CO2

Now divide the 32.65 g O2 by the molar mass of O2 (32.00 g/mol) to get moles of O2. Then multiply by the mole ratio of 2 mol CO for every 1 mol O2 to get moles of CO needed to fully react.

32.65 g O2 / 32.00 g/mol = 1.020 mol O2

1.020 mol O2 • 2 mol CO / 1 mol O2 = 2.040 mol CO

Answer:

X5Y2

Explanation:

% composition of X = 52.2%

% composition of Y = (100 - 52.2) = 47.8%

This means that there are 52.2g of X and 47.8g of Y in the compound

To calculate the empirical formula of the compound, we first convert the gram value to mole value by dividing by their molar masses.

X = 52.2g/42.3g/mol = 1.234mol

Y = 47.8g/96.7g/mol = 0.494mol

Next, we divide each mole value by the smallest value (0.494mol)

X = 1.234mol ÷ 0.494mol = 2.49

Y = 0.494mol ÷ 0.494mol = 1

We multiply each value by 2

X = 2.49 × 2 = 4.98

Y = 1 × 2 = 2

The simple ratio of X:Y is 5:2, hence, their empirical formula is X5Y2.

Answer:a

Explanation:

Answer:

A

Explanation:

Answer:

the answer for this one is the distance the car is driven

Answer: It does not react with water, but reacts with most acids. It combines with oxygen at room temperature to form chromium oxide. Chromium oxide forms a thin layer on the surface of the metal, protecting it from further corrosion (rusting).

Explanation:

Answer:

Option D, Index fossil helps scientists to determine the relative ages of rocks by their positions

Explanation:

Index fossils are arranged in layer in such a way that the lowest layer represent the oldest fossil and the top most layer represents the youngest fossil. Scientist use this concept to determine the relative age of the rocks based on their position beneath the earth’s surface

Hence, option D is correct

Answer:

35750.4 Joules

Explanation:

Using the formula as follows;

Q = m × c × ∆T

Where;

Q = amount of heat (joules)

m = mass of substance (g)

c = specific heat capacity (J/g°C)

∆T = change in temperature (°C)

According to the provided information,

mass (m) = 320.0 grams

c = 4.2 J/g°C

∆T = (50.8°C - 24.2°C) = 26.6°C

Q = ?

Using; Q = m × c × ∆T

Q = 320 × 4.2 × 26.6

Q = 35750.4 J

Answer:

Ionic compounds generally form between elements that are metals and elements that are non metals. For example, the metal calcium (Ca) and the non metal chlorine (Cl) form the ionic compound calcium chloride (CaCl2). In this compound, there are two negative chloride ions for each positive calcium ion.

Explanation:

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Answer:

48 grams

Explanation:

The chemical equation for the reaction is the following:

2 H₂ + O₂ → 2 H₂O

That means that 2 moles of H₂ react with 1 mol of O₂ to produce 2 moles of H₂O. We convert the moles of oxygen (O₂) by using the molecular weight (MW) as follows:

MW(O₂) = 16 g/mol x 2 = 32 g/mol

mass of O₂ = 1 mol x 32 g/mol = 32 g

So, we have the following stoichiometric ratio: 32 g O₂/2 moles H₂. We have 3 moles of hydrogen (H₂), so we multiply the moles by the stoichiometric ratio to calculate how many grams are needed:

3 moles H₂ x 32 g O₂/2 moles H₂ = 48 g O₂

Therefore, 48 grams of O₂ are needed to react with 3 moles of H₂.

The volume (in litres) of 2.75 g of fluorine gas at 35 °C and 4.55 atm is 0.402 L

Mole = mass / molar mass

Mole of F₂ = 2.75 / 38

Mole of F₂ = 0.0724 mole

Using the ideal gas equation, the volume of the gas can be obtained as follow:

PV = nRT

Divide both side by P

V = nRT / P

V = ( 0.0724 × 0.0821 × 308) / 4.55

V = 0.402 L

Learn more about ideal gas equation:

https://brainly.com/question/4147359

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

Answer:

B

Explanation:

1 mole is equal to 58.31968 grams.

so 3.5 moles equal to answer choice B

Answer: Some are solid, some are gaseous, a few are liquid. Some are metallic: they have a peculiar lustre; some are coloured (like sulfur) or colourless. Some have a low density; some have a high density. Some are malleable and ductile; some are brittle. Some conduct electricity and heat well; some don’t.

Many metals tend to have structural uses. Nonmetallic elements less so.

Metals tend to have crystal forms featuring close-packed centro-symmetrical structures. Nonmetallic elements tend to have crystal structures featuring more open and directionally packed structures.

Some are especially toxic; some are essential to life; some are both depending on exposure level.

Most are stable; some are less so.

Some elements are highly reactive; some are almost inert (helium, neon, and argon may be completely inert in ambient conditions).

Many metals have basic oxides; quite a few oxides of nonmetallic elements form acids when they are dissolved in water. Some elements can go both ways.

There are many generalisations you can make about metallic and nonmetallic elements, and quite a few exceptions at the margins.

Explanation:

State and explain the three basic properties of element.

Some properties of an element can be observed only in a collection of atoms or molecules of the element. These properties include color, density, melting point, boiling point, and thermal and electrical conductivity.

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Answered by - ItzMaster

Answer:

Photosynthesis

Explanation:

Photosynthesis uses energy from light to convert water and carbon dioxide molecules into glucose (sugar molecule) and oxygen. The oxygen is released, or “exhaled”, from leaves while the energy contained within glucose molecules is used throughout the plant for growth, flower formation, and fruit development.

Answer:

rn4y8rg7348y0rp934nrf3

efjewhrf8h934hfr84398wgfyu8o

Explanation:

fe8u34h4n3urhu93q4pirnpqr34uwbry8439br8u3i2rpi34ofreuebue rf ef erf3rw  wg

Answer:

An acidic solution has a high concentration of hydrogen ions (H +start superscript, plus, end superscript), greater than that of pure water.

The acidic solution indicates the highest concentration of hydrogen or the proton ion in the solution.

Acidity is the measure of the hydrogen ion in the solution by the pH scale and gives the acidic or basic characteristics to the solution.

The concentration of the hydronium or the hydroxide in the solution is a way to determine the acidic basic nature and the pH and pOH of the solution.

Therefore, in an acidic solution hydrogen ions are in the greatest concentration.

Learn more about acid here:

https://brainly.com/question/24194581

#SPJ2

Answer:

between 5.0 and 5.5

Explanation:

acidic

Answer:

670.45 K

Explanation:

Given that,

Initial volume, V₁ = 1.22 L

Initial temperature, T₁ = 286 K

Final volume, V₂ =  2.86 L

We need to find the new temperature of the gas. The relation between the volume and the temperature is given by :

[tex]\dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}\\\\T_2=\dfrac{V_2T_1}{V_1}\\\\T_2=\dfrac{2.86\times 286}{1.22}\\\\T_2=670.45\ K[/tex]

So, the new temperature of the gas is equal to 670.45 K.

Answer:

7.89 grams of phosphorus reacts with 45.15 grams of chlorine

Explanation:

For reacting with 2 mole of P react with 5 mole of Cl2 gas

Molecular weight of phosphorus = 30.97

Molecular weight of 2 mole of phosphorus = 2 * 30.97 = 61.94 grams

Molecular weight of Chlorine molecule = 70.9 grams

Weight of 5 moles of Chlorine molecule = 5 * 70.9 grams = 354.5 grams

61.94 grams of phosphorus reacts with 354.5 grams of chlorine

7.89 grams of phosphorus reacts with 354.5/61.94 * 7.89  grams of chlorine

7.89 grams of phosphorus reacts with 45.15 grams of chlorine

Answer: it’s D

Explanation:an event that provokes a specific functional response in an organ or tissue of an organism is called as stimulus

hope it helps

Answer:

B and I think A but you may want a secon opinion on that

Explanation:

I know that electrons are shared with covalent bonds so I assume the 2 answers are the ones with electrons it them

Answer:

149.79 grams.

Explanation:

Formula

Joules = m * c * delta (t)

Givens

J = 28242

m = ?

c = 4.19

Δt = 63 - 18 = 45

Solution

28242 = m * 4.19 * 45

28242 = m * 188.55

m = 28242 / 188.55

m = 149.79

Answer:

C. Nervous

Explanation:

The nervous system is a system of the body of living organisms which includes the brain, spinal cord and nerves.

Answer:

earth

Explanation: