Questions and task on the subject Chemistry

Questions and task on the subject Chemistry

Identify which of the following statements are TRUE. The composition of a pure substance is variable. The density of a pure substance is fixed. The properties of mixtures are con...

28.09.2022 03:10

3 answer(s)

Why are the atomic masses of isotopes different?...

25.09.2022 02:10

1 answer(s)

If the distance between 2 objects increased, what would happen to the force of gravity between them....

22.09.2022 14:00

2 answer(s)

Particles, or atoms, in a high-pressure gas are exerting container. O minimal thermal constant large forces on the *...

17.09.2022 20:10

1 answer(s)

Cobalt has 27 electrons-27 protons and Iron has 26 electrons-26 protons. Which answer is correct? A) Iron and Cobalt atoms attract since they don't have the same number of electr...

14.09.2022 01:10

1 answer(s)

Distinguish between the terms solute, solvent and solution?...

09.09.2022 14:00

1 answer(s)

If 0.896 g of a gas occupies a 250 mL flask at 20°C and 760 mm Hg of pressure, what is the molar mass of the gas?...

05.09.2022 14:00

2 answer(s)

The reaction below is at equilibrium. What would happen if more carbon were added? C(s) + O₂(g) CO₂(g)...

01.09.2022 18:20

2 answer(s)

The following balanced equation represents what type of reaction? 2 H2O → 2 H2 + O2 Select one: a. double displacement b. single displacement c. synthesis d. decomposition...

31.08.2022 03:00

1 answer(s)

6. a) Define the term pH...

19.08.2022 04:30

1 answer(s)

You are given 100 g of a compound. The compound is composed of 37% hydrogen and 63% oxygen. How many grams oxygen are present in the 100 g sample? Select one: a. 37 g b. 100 g c. 2...

12.08.2022 14:00

1 answer(s)

Calculate the number of atoms in 3 mol helium...

11.08.2022 06:10

2 answer(s)

Write a careful description of a metal or an alloy . Use the correct scientific terms. Explain which properties of metals are particularly suited to the function it has. a) The n...

11.08.2022 04:40

3 answer(s)

One way to determine the age of the earth is to measure the ratio of certain radioactive elements to their more stable forms. By comparing the amount of radioactive form of an obje...

11.08.2022 01:40

2 answer(s)

A piece of copper absorbs 5000 J of energy and undergoes a temperature change from 100 °C to 200 °C. What is the mass of the piece of copper? Group of answer choices A. 12.9 gram...

09.08.2022 03:10

2 answer(s)

In nature, X contains two isotopes with mass numbers 79 and 81. Calculate the percentage abundance of the isotopes ⁷⁹X and ⁸¹X....

08.08.2022 22:10

2 answer(s)

6) What is the pH of a solution with [H3O+] = 1 × 10-9 M? A) 1.0 × 10-5 B) -9.0 C) 5.0 D) -5.0 E) 9.0...

08.08.2022 17:40

1 answer(s)

Increased total serum lactic dehydrogenase (LD) activity, confined to fractions 4 and 5 is most likely to be associated with: A. Pulmonary infarction B. Hemolytic anemia C. Myocard...

07.08.2022 20:30

3 answer(s)

Write the balanced redox reaction Fe2+ and MnO4...

07.08.2022 14:00

2 answer(s)

Find the amount of heat energy needed to convert 400 grams of ice at -38°C to steam at 160°C. Group of answer choices A. 246840 Joules B. 159984 Joules C. 331056 Joules D. 128444...

06.08.2022 18:20

2 answer(s)

Hypernatremia due to excess water loss: A. Diabetes insipidus B. Dialysis fluid excess C. Hyperaldosteronism D. Older persons...

06.08.2022 16:40

2 answer(s)

Write equations that show NH3 as both a conjugate acid and a conjugate base....

06.08.2022 16:10

1 answer(s)

What is the pH of a 0.0100 M sodium benzoate solution? Kb (C7H5O2-, ) = 1.5 x 10^-10 A) 0.38 B) 5.91 C) 8.09 D) 9.82 E) 13.62...

06.08.2022 06:20

3 answer(s)

In Keq expressions, "[]" represents of reactants and products. a)concentration b)temperature c)moles d)mass...

05.08.2022 02:20

3 answer(s)

Can someone help me create energy diagrams for these three reactions?...

05.08.2022 01:00

1 answer(s)

Find the amount of heat energy needed to convert 150 grams of ice at -15°C to ice at -63°C. Group of answer choices A. (-) 14760 Joules because the ice is being heated. B. (-) 14...

04.08.2022 19:00

3 answer(s)

Lactic acid has a pKa of 3.08. What is the approximate degree of dissociation of a 0.35 M solution of lactic acid? A) 1.1% B) 2.2% C) 4.8% D) 14% E) none of the above...

01.08.2022 15:30

2 answer(s)

The well data sheet is provided. Please estimate the volume of biocide needed to batch treat the water above top perforations in the whole casing after ESP is removed from the well...

31.07.2022 23:50

1 answer(s)

Which term describes the amount of pressure each gas in a mixture contributes to the overall gas pressure?...

31.07.2022 15:30

2 answer(s)

chegg cytosine Draw the three different conjugate acids if each of those three nitrogens are protonated....

30.07.2022 22:30

3 answer(s)

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