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
sergey [27]
3 years ago
12

Which of the following is an element? A. CO2 B. H2O C. Xy D. Na

Chemistry
1 answer:
max2010maxim [7]3 years ago
3 0
I believe the answer is D
You might be interested in
A golfer hits a golf ball with a club. The mass of the ball is 0.05 kg. The ball accelerates at
Alex73 [517]

Answer:

100 n im just guess

Explanation:

if it helps.

have a good day

hope you stay safe

4 0
3 years ago
How does the amount of carbon dioxide affect the rate of photosynthesis?
julsineya [31]

Answer:

There are several ways of measuring the rate of photosynthesis in the lab. These include:

the rate of oxygen output

the rate of carbon dioxide uptake

the rate of carbohydrate production

These are not perfect methods as the plant will also be respiring, which will use up some oxygen and carbohydrate and increase carbon dioxide output.

Several factors can affect the rate of photosynthesis:

light intensity

carbon dioxide concentration

temperature

The amount of chlorophyll also affects the rate of photosynthesis:

plants in lighting conditions unfavourable for photosynthesis may synthesise more chlorophyll, to absorb the light required

the effects of some plant diseases affect the amount of chlorophyll, and therefore the ability of a plant to photosynthesise

hope it helps you

4 0
3 years ago
Consider the decomposition of red mercury(II) oxide under standard state conditions. )H0 T SFE ڮ( H M 0 H (a) Is the decompositi
sertanlavr [38]

The question is incomplete, complete question is :

Consider the decomposition of red mercury(II) oxide under standard state conditions.

2HgO(s)\rightarrow 2Hg(l)+O_2(g)

Given :

\Delta S_{HgO}^o=70.29 J/mol K

\Delta S_{Hg}^o=75.9 J/mol K

\Delta S_{O_2}^o=205.2 J/mol K

Enthalpy change of the reaction = ΔH = -90.83 kJ/mol

(a) Is the decomposition spontaneous under standard state conditions?

(b) Above what temperature does the reaction become spontaneous?

Answer:

a) The decomposition is spontaneous under standard state conditions.

b)The reaction will spontaneous above -419.69 Kelvins.

Explanation:

2HgO(s)\rightarrow 2Hg(l)+O_2(g)

Given :

\Delta S_{HgO}^o=70.29 J/mol K

\Delta S_{Hg}^o=75.9 J/mol K

\Delta S_{O_2}^o=205.2 J/mol K

Entropy change of the reaction ; ΔS

\Delta S=[2\times \Delta S_{Hg}^o+1\times \Delta S_{O_2}^o]-[2\times \Delta S_{HgO}^o]

=[2\times 75.9 J/mol K+1\times 205.2 J/molK]-[2\times 70.29 J/molK]=216.42 J/mol K

Enthalpy change of the reaction = ΔH = -90.83 kJ/mol  = -90830 J/mol K

1 kJ = 1000 J

At standard condition the value of temperature = T = 298 K

ΔG = ΔH - TΔS

ΔG = -90830 J/mol K - 298 K × 216.42 J/mol K = -155,323.16 J/mol

ΔG < 0 ( spontaneous)

The decomposition is spontaneous under standard state conditions.

b) Above what temperature does the reaction become spontaneous

Let the ΔG = 0

Enthalpy change of the reaction = ΔH = -90.83 kJ/mol  = -90830 J/mol K

ΔG = ΔH - TΔS

0 = -90830 J/mol K - T × 216.42 J/mol K

T = -419.69 K

The reaction will spontaneous above -419.69 Kelvins.

6 0
3 years ago
What element is probably most<br> like oxygen and why
Dmitrij [34]
Any elements in the same periodic group as oxygen such as sulfur, as elements are grouped together through similar properties
4 0
1 year ago
Obsidian is a volcanic glass that forms when lava cools very quickly and consists of a solid mass of glass through and through.
Alecsey [184]

Answer:

Obsidian is not a mineral as the atoms or molecules in obsidian do not have a crystalline structure.

Explanation:

Obsidian originates naturally and is formed by igneous rock.

When felsic larva comes out from the volcano,it rapidly cools down and thus form obsidian.It is pure black in color but some times color differ due to presence of some impurities.

It is brittle,but hard.It is not a mineral and is called as mineraloids and is not found in crystalline form,.

The main constituent is SiO2.

It is found in the margin of rhyolitic lava.

6 0
3 years ago
Other questions:
  • The stopcock connecting a 2.25 L bulb containing oxygen gas at a pressure of 4.00 atm, and a 5.25 L bulb containing neon gas at
    12·1 answer
  • How does a convection current circulate a fluid?
    15·1 answer
  • Which of the following changes will slow down a reaction?
    12·1 answer
  • Perform the given operation and report the answer with the appropriate number of significant figures. 4.910 km - 0.08 km = ?
    9·1 answer
  • An unknown sample of mystery element T is analyzed. According to the data 7.42% of the element is ^6T and 92.58% is ^7T. The tru
    12·1 answer
  • Which of the following elements has the smallest atomic radius?
    14·2 answers
  • Which particles determines the name of the element?
    14·1 answer
  • if the side if a chemical equation has 3, carbon atoms, 6 oxygen atoms and 4 hydrogen atoms then the right side of the chemical
    5·1 answer
  • What is the amount of energy that holds the protons and neutrons together in the nucleus?
    6·1 answer
  • What could humans do to make enough oxygen to survive?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!