The column just before the stable noble gases are called the

Nataly [62]

Answer:

C. An organized way to test scientific ideas.

Explanation:

The Scientific Method is a series of steps to test ideas and hypothesizes. We use the Scientific Method to make it easier to organize and label things step by step.

8 0

3 years ago

Small quantites of hydrogen gas can be prepared in the laboratory by the addition of aqueous hydrochloric acid to metallic zinc.

ira [324]

<u>Answer:</u> The mass or zinc reacted is 0.624 grams.

<u>Explanation:</u>

We are given:

Total pressure = 1.032 atm

Vapor pressure of water = 32 torr = 0.042 atm (Conversion factor: 1 atm = 760 torr)

To calculate partial pressure of hydrogen gas, we use the equation:

$p_{H_2}=p_T-p_{H_2O}\\\\p_{H_2}=1.032-0.042=0.99atm$

To calculate the number of moles of hydrogen gas, we use the equation given by ideal gas follows:

$PV=nRT$

where,

P = pressure of hydrogen gas = 0.99 atm

V = Volume of hydrogen gas = 240. mL = 0.240 L (Conversion factor: 1 L = 1000 mL)

T = Temperature of hydrogen gas = $30^oC=[30+273]K=303K$

R = Gas constant = $0.0821\text{ L. atm }mol^{-1}K^{-1}$

n = number of moles of hydrogen gas = ?

Putting values in above equation, we get:

$0.99atm\times 0.240L=n\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 303K\\n=\frac{0.99\times 0.240}{0.0821\times 303}=9.55\times 10^{-3}mol$

The chemical equation for the reaction of zinc and hydrochloric acid follows:

$Zn+2HCl\rightarrow ZnCl_2+H_2$

By Stoichiometry of the reaction:

1 mole of hydrogen gas is produced from 1 mole of zinc metal

So, $9.55\times 10^{-3}mol$ of hydrogen gas is produced from = $\frac{1}{1}\times 9.55\times 10^{-3}=9.55\times 10^{-3}mol$ of zinc metal

To calculate the mass of zinc metal, we use the equation:

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

Molar mass of zinc = 65.38 g/mol

Moles of zinc = $9.55\times 10^{-3}$ moles

Putting values in above equation, we get:

$9.55\times 10^{-3}mol=\frac{\text{Mass of zinc}}{65.38g/mol}\\\\\text{Mass of zinc}=(9.55\times 10^{-3}mol\times 65.38g/mol)=0.624g$

Hence, the mass or zinc reacted is 0.624 grams.

4 0

3 years ago

at what height is an object that has a mass of 16kg, if it’s gravitational potential energy is 7500J?

dolphi86 [110]

Answer:

46.875

Explanation:

P.E=MGH

7500=16*10*h

7500=160h

h=7500/160

h=46.875

5 0

3 years ago

Which property would be characteristic of a non-metal?

RideAnS [48]

I think the answer is B.
I know the answer cant be A because a lot of metal that is new can be shiny.
C is incorrect because malleable means that it can be permanently bent out of shape ( which metal can be )
D is incorrect because a lot of metal can conduct electricity for example copper and brass can both conduct electricity
<span />

5 0

3 years ago

Read 2 more answers

A chemist wants to calculate the amount of heat that is absorbed by a sample of copper as it is melted. Which constant should sh

34kurt

The constant used for the absorption of heat by the sample in melting is $+\Delta H_{fus}$ . Thus, option A is correct.

The chemical reaction has been defined as the energy in which the energy has been released or absorbed for the breaking of bonds in the reactants and the formation of product.

<h3>Constant for energy absorbed</h3>

The energy has been absorbed in the melting of the copper sample. Thus, the sample has been converted from the solid to the liquid state.

The change in energy with the conversion in solid and liquid state has been termed as heat of fusion.

The energy has been absorbed by the system, thus it has been marked with the positive sign.

Therefore, $+\Delta H_{fus}$ has been the constant used for the absorption of heat by the sample in melting. Thus, option A is correct.

Learn more about melting sample, here:

brainly.com/question/8828503

8 0

2 years ago