All categories

3 years ago

Please help I’ll brainleist you

Chemistry

1 answer:

NARA [144]3 years ago

8 0

Answer:

1. They can tell that a reaction has taken place if there is formation of gas bubbles in the test tube as well as if the metal dissolves in the acid solution

2. To determine which metal is more reactive, they would compare how fast each reaction occurs. The most reactive metal would have the fastest rate of reaction with a vigorous formation of bubbles, whereas the least reactive metal will have the slowest rate of reaction.

Explanation:

1. Metal which are more electropositive than hydrogen displace hydrogen from dilute acids with the formation of the salt of the metal and evolution of hydrogen gas. Therefore, the formation of gas bubbles in the test tube indicates that a reaction is taking place.

2. The rate of formation of the gas bubbles as well as the time taken for the reaction to come to a completion by the dissolution of the metal in the acid indicates which metal is more reactive. The most reactive metal would have the fastest rate of reaction with a vigorous formation of bubbles, whereas the least reactive metal will have the slowest rate of reaction.

However, the rate of the reaction is also affected by the concentration of the acid used. The higher the concentration of the acid, the faster the reaction rate.

You might be interested in

Swim ability is it materials ability to burn in the presence of

eduard

Answer: Flammability is a material's ability to burn in the presence of oxygen.

Explanation: Chemical properties can be observed only when the substance changes into one or more different substances through chemical reactions or transformations. One of the chemical properties is flammability.

Flammability is a material's ability to burn in the presence of oxygen.

Remember, oxygen doesn't burn. Precisely flammable substances obtain substances that burn. Oxygen remains an oxidizing agent, which means it supports the combustion process. Oxygen causes other objects to catch fire at low temperatures and burns hotter and faster. But oxygen itself does not burn. Consequently, if you at present deliver fuel and fire, adding oxygen will provide the fire.

Carbon dioxide is the result of combustion. An example can be seen in firewood in a fireplace. One of the chemical properties of carbon-based wood is having the ability to burn. Chemically the wood turns into carbon dioxide when it burns and leaves a residue of ash. Furthermore, this ash residue cannot be turned back into the wood. Chemical changes result in new substances.

Consider an example of a combustion reaction to methane gas:

Our balanced equation for methane combustion implies that every one CH₄ molecule reacts with two O₂ molecules. The product of combustion is one carbon dioxide molecule and two steam or water vapor molecules.

6 0

3 years ago

Why is 99 not a prime number

Mice21 [21]

Explanation:

99 is not a prime number because it can be multiplied by itself and by other numbers

99*1

9*11

6 0

3 years ago

Read 2 more answers

Suppose of copper(II) acetate is dissolved in of a aqueous solution of sodium chromate. Calculate the final molarity of acetate

uranmaximum [27]

Answer:

0.0714 M for the given variables

Explanation:

The question is missing some data, but one of the original questions regarding this problem provides the following data:

Mass of copper(II) acetate: $m_{(AcO)_2Cu} = 0.972 g$

Volume of the sodium chromate solution: $V_{Na_2CrO_4} = 150.0 mL$

Molarity of the sodium chromate solution: $c_{Na_2CrO_4} = 0.0400 M$

Now, when copper(II) acetate reacts with sodium chromate, an insoluble copper(II) chromate is formed:

$(CH_3COO)_2Cu (aq) + Na_2CrO_4 (aq)\rightarrow 2 CH_3COONa (aq) + CuCrO_4 (s)$

Find moles of each reactant. or copper(II) acetate, divide its mass by the molar mass:

$n_{(AcO)_2Cu} = \frac{0.972 g}{181.63 g/mol} = 0.0053515 mol$

Moles of the sodium chromate solution would be found by multiplying its volume by molarity:

$n_{Na_2CrO_4} = 0.0400 M\cdot 0.1500 L = 0.00600 mol$

Find the limiting reactant. Notice that stoichiometry of this reaction is 1 : 1, so we can compare moles directly. Moles of copper(II) acetate are lower than moles of sodium chromate, so copper(II) acetate is our limiting reactant.

Write the net ionic equation for this reaction:

$Cu^{2+} (aq) + CrO_4^{2-} (aq)\rightarrow CuCrO_4 (s)$

Notice that acetate is the ion spectator. This means it doesn't react, its moles throughout reaction stay the same. We started with:

$n_{(AcO)_2Cu} = 0.0053515 mol$

According to stoichiometry, 1 unit of copper(II) acetate has 2 units of acetate, so moles of acetate are equal to:

$n_{AcO^-} = 2\cdot 0.0053515 mol = 0.010703 mol$

The total volume of this solution doesn't change, so dividing moles of acetate by this volume will yield the molarity of acetate:

$c_{AcO^-} = \frac{0.010703 mol}{0.1500 L} = 0.0714 M$

8 0

3 years ago

Which statement about silver Ag metal is least reliable

Anna007 [38]

<span>The choices for this question can be found elsewhere and as follows:

Silver is a transition metal with electrons in the d shell.
Silver atoms have 47 protons in their nuclei.
Silver atoms commonly form ions with a +1 charge.

I think the correct answer is the last option. The least reliable information would be that s</span>ilver atoms commonly form ions with a +1 charge.

3 0

3 years ago

Read 2 more answers

What is the difference between a heterogeneous mixture and homogeneous mixture?

Fiesta28 [93]

A homogeneous mixture has the same uniform appearance and composition throughout

A heterogeneous mixture consists of visibly different substances or phases.

7 0

3 years ago