The least condensed state of matter is

A camcorder has a power rating of 11 watts. If the output voltage from its battery is 8 volts, what current does it use?

Reika [66]

The camcorder uses a current of 1.4 A.

P = VI

I = P/V = 11 W/8 V = 1.4 A

Note: The answer can have only one significant figure because that is all you gave for the voltage. However, I calculated the current to two significant figures.

3 0

3 years ago

For a theoretical yield of 23 g and actual

solong [7]

Answer:

5. 56.5217

Explanation:

Calculate percent yield by (actual yield / theoretical yield) times 100

(13/23) x 100 = 56.52173913

6 0

3 years ago

Zinc dissolves in hydrochloric acid to yield hydrogen gas: zn(s) + 2hcl(aq) → zncl2(aq) + h2(g) when a 12.7 g chunk of zinc diss

N76 [4]

First calculate the initial moles of HCl.

HCl moles i = (1.45 moles / L) * 0.5 L = 0.725 moles HCl

Then calculate how much HCl is consumed by stoichiometry:

HCl moles consumed = (12.7 g Zn / 65.38 g / mol) * (2 moles HCl / 1 mole Zn) = 0.388 moles

So HCl moles left is:

HCl moles f = 0.725 – 0.388 = 0.3365 moles

For every 1 mole HCl there is 1 mole H, therefore:

H moles final = 0.3365 moles

So final concentration of H ions is:

Concentration H = 0.3365 moles / 0.5 L = 0.673 M

4 0

3 years ago

An element, X, can form a chloride (XCl3) and an iodide (XI3). The chloride can be converted quantitatively into the iodide when

Arlecino [84]

Answer : The chemical symbol for this element is, (La)

Explanation : Given,

Mass of $XCl_3$ = 0.760 g

Mass of $XI_3$ = 1.610 g

The given chemical reaction is:

$2XCl_3+3I_2\rightarrow 2XI_3+3Cl_2$

First we have to calculate the moles of $XCl_3$ and $XI_3$ .

$\text{Moles of }XCl_3=\frac{\text{Mass of }XCl_3}{\text{Molar mass of }XCl_3}$

Molar mass of Cl = 35.5 g/mole

Let the molar mass of element 'X' be, M

$\text{Moles of }XCl_3=\frac{0.760}{[M+3(35.5)]}$

and,

$\text{Moles of }XI_3=\frac{\text{Mass of }XI_3}{\text{Molar mass of }XI_3}$

Molar mass of I = 126.9 g/mole

Let the molar mass of element 'X' be, M

$\text{Moles of }XI_3=\frac{1.610}{[M+3(126.9)]}$

From the balanced chemical reaction we conclude that,

The moles of ratio of $XCl_3$ and $XI_3$ is, 1 : 1

That means,

$\frac{0.760}{[M+3(35.5)]}=\frac{1.610}{[M+3(126.9)]}$

$\frac{0.760}{[M+106.5]}=\frac{1.610}{[M+380.7]}$

$M=138.667g/mol$

From this we conclude that the element (X) is lanthanum (La) that has molecular weight, 138.667 g/mol.

Hence, the chemical symbol for this element is, (La)

6 0

4 years ago

For the following reaction, 5.78 grams of chlorine gas are mixed with excess iron. The reaction yields 6.79 grams of iron(III) c

NeX [460]

Answer:

a. Theoretical yield = 8.81 g

b. 77 %

Explanation:

We begin from the reaction:

2Fe (s) + 3Cl₂ (g) → 2FeCl₃ (s)

and the excess is the iron, so the limiting reagent is the chlorine.

We convert mass to moles → 5.78 g / 70.90 g/mol = 0.0815 mol

Ratio is 3:2 so we think this:

From 3 moles of chlorine, I can produce 2 moles of Iron (III) chloride

Then 0.0815 moles would produce (0.0815 . 2) /3 = 0.0543 moles

This is the theoretical yield. We convert the moles to mass:

0.0543 mol . 162.2 g /mol = 8.81 g

If the reaction yields 6.79 g of FeCl₃ and the theoretical yield is 8.81 g ,we can obtain the percent yield: (6.79 / 8.81) . 100 = 77 %

5 0

3 years ago