All categories

3 years ago

If a compound pulley has four

Chemistry

1 answer:

NeTakaya3 years ago

8 0

Answer:

With four rope segments, the ideal mechanical advantage is 4. This means that the compound pulley multiplies the force applied to it by a factor of 4.

Explanation:

You might be interested in

Plsss help me!!! ASAP!!!

Arisa [49]

Answer:

I think the answer is D...

8 0

3 years ago

A boy found a solid metal box in his backyard. The box had been buried for so long, it was difficult to determine from what the

Alex777 [14]

Answer:

Box is made up of <em>copper</em>, because density is <em>8.96 g/cm³.</em>

Explanation:

Given data:

Volume of box = 17.63 cm³

Mass of box = 158 g

Which metal box is this = ?

Solution:

First we will calculate the density of box then we will compare it with the density value of given metals.

d = m/v

d = 158 g/ 17.63 cm³

d = 8.96 g/cm³

The calculated density is similar to the given density value of copper thus box is made up of copper.

4 0

4 years ago

The pKb values for the dibasic base B are pKb1=2.10 and pKb2=7.54. Calculate the pH at each of the points in the titration of 50

AveGali [126]

Complete Question

The pKb values for the dibasic base B are pKb1=2.10 and pKb2=7.54. Calculate the pH at each of the points in the titration of 50.0 mL of a 0.60 M B(aq) solution with 0.60 M HCl(aq).

(a) before addition of any HCl (b) after addition of 25.0 mL of HCl

Answer:

a The value is $pH =12.81$

b $pH = 11.9$

Explanation:

From the question we are told that

The first pKb value for B is $pK_b_1 = 2.10$

The second pKb value for B is $pK_b_2 = 7.54$

The volume is $V = 50.0 mL =$

The concentration of B is $[B] = 0.60 M$

The concentration of $C_A = 0.60 M$

Generally the reaction equation showing the first dissociation of B is

$\ce{B_{(aq) } + H_2O _{(l)} BH^+ _{(aq)} + OH^- _{(aq)} }$

Here the ionic constant for B is mathematically represented as

$K_i = \frac{[BH^+] [OH^-]}{[B]}$

Let denot the concentration of [BH^+] as z and since $[BH^+] = [OH^-]$ then $[OH^-]$ is also z

So [B] = 0.60 - z

Here $K_i$ is ionic constant for the first reaction of a dibasic base B and the value is

$K_i = 7.94 *10^{-3}$

$7.94 *10^{-3}= \frac{z^2}{ 0.60 - z}$

=> $z^ 2 + 0.00794 z - 0.00476$

using quadratic formula to solve this equation

$z = 0.0651$

Hence the concentration of $OH^{-}$ is $[OH^-] =0.0651$

Generally $pOH = -log [OH^-]$

=> $pOH = -log (0.065)$

=> $pOH = 1.187$

Generally the pH is mathematically represented as

$pH = 14 - 1.187$

$pH =12.81$

Generally the volume of $HCl$ at the second dissociation of the base B is $50 mL$

The volume of the $HCl$ half way to the first dissociation of the base is 25mL

Now the pOH at half way to the first dissociation of the base is

$pOH = -log(K_i)$

=> $pOH = -log(0.00794)$

=> $pOH = 2.100$

Generally the pH after addition of 25.0 mL of HCl is

$pH = 14 - 2.100$ \

=> $pH = 11.9$

4 0

3 years ago

Find the pH of a 0.0000734 M solution of HI

dedylja [7]

Answer:

pH of the HI solution =4.13 .

Explanation:

0.0000734 M concentration of Hl is the same as saying that 7.34 *10-5 moles of H+ ions have been added to solution.

pH of HI = -log[H+]

The -log[0.0000734] =4.1343.

pH of the HI solution =4.13.

5 0

4 years ago

The periodic table is a chart that uses

Y_Kistochka [10]

Explanation:

The periodic table presents an orderly arrangement of elements based on their atomic numbers.

The modern periodic table is established on the periodic law which states that "the properties of elements are a periodic function of their atomic number".

On the table, elements having the same number of electrons in the outermost shell of their atoms are placed over one another in the vertical column. Each vertical column is known as group and the horizontal column is known as period.

Learn more:

Periodic table brainly.com/question/2014634

Regions of the table brainly.com/question/2014634

#learnwithBrainly

3 0

3 years ago