Where are human cells located (in living organisms)

Pb(OH)Cl, one of the lead compounds used in ancient Egyptian cosmetics, was prepared from PbO according to the following recipe:

sladkih [1.3K]

Answer:

8.59 g

2.25 g

Explanation:

According to the given situation the calculation of grams of PbO and grams of NaCL is shown below:-

Moles of Pb(OH)CL is

$= \frac{Mass}{Molar\ mass}$

$= \frac{10.0 g}{259.65g / mol}$

= 0.0385 mol

Mass of PbO needed is

$= 0.385mol Pb(OH) Cl\times \frac{1 mol PbO}{1molpb (OH) cl} \times \frac{223.2g PbO}{1mol PbO}$

After solving the above equation we will get

= 8.59 g

Mass of NaCL needed is

$= \frac{1mol\ NaCl}{1molPb\ (OH)Cl} \times \frac{58.45NaCl}{1mol NaCl}$

After solving the above equation we will get

= 2.25 g

Therefore we have applied the above formula.

7 0

3 years ago

Which is correct if 15,390,000 is rounded to two significant figures?

BARSIC [14]

Answer:

Explanation:

Remark

This is one of those questions that you need the choices. You can't tell what you should enter. For example, in scientific notation, you would get 1.5*10^7.

Or you could keep it as an integer and round to two places 150,000,000,

I would pick scientific notation if you know how to use it. Otherwise use the interger format.

7 0

2 years ago

A cheetah is an organism that observes chase and catches its pery what kind of energy is that A mechanicle kenetic to chemical t

Temka [501]

Answer:

C mechanical potential to chemical to mechanical kinetic

Explanation:

When the cheetah observes it prey, it does not move at all and remains still in one place. This is potential energy.

To chase after its prey or to pounce on it, the cheetah would require energy. This is obtained by its body by performing certain chemical activities that generate energy that help it to move.

When the cheetah finally undergoes this, it has enough energy to finally come out of hiding and chase its prey. This is kinetic energy as while doing so, the cheetah is in motion.

Hope it helps.

4 0

3 years ago

A 1.2 L weather balloon on the ground has a temperature of 25°C and is at atmospheric pressure (1.0 atm). When it rises to an el

icang [17]

Answer:

The temperature of the air at this given elevation will be 53.32425°C

Explanation:

We can calculate the final temperature through the combined gas law. Therefore we will need to know 1 ) The initial volume, 2 ) The initial temperature, 3 ) Initial Pressure, 4 ) Final Volume, 5 ) Final Pressure.

Initial Volume = 1.2 L ; Initial Temperature = 25°C = 298.15 K ; Initial pressure = 1.0 atm ; Final Volume = 1.8 L ; Final pressure = 0.73 atm

We have all the information we need. Now let us substitute into the following formula, and solve for the final temperature ( T $_2$ ),

P $_1$ V $_1$ / T $_1$ = P $_2$ V $_2$ / T $_2$ ,

T $_2$ = P $_2$ V $_2$ T $_1$ / P $_1$ V $_1$ ,

T $_2$ = 0.73 atm $*$ 1.8 L $*$ 298.15 K / 1 atm $*$ 1.2 L = ( 0.73 $*$ 1.8 $*$ 298.15 / 1 $*$ 1.2 ) K = 326.47425 K,

T $_2$ = 326.47425 K = 53.32425 C

7 0

3 years ago

Explain what a conjugate acid is and what a conjugate base is.

Svetlanka [38]

Answer:

A conjugate acid, within the Brønsted–Lowry acid–base theory, is a chemical compound formed when an acid donates a proton to a base—in other words, it is a base with a hydrogen ion added to it, as in the reverse reaction it loses a hydrogen ion

Explanation:

7 0

3 years ago

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