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2 years ago

A screw is an example of a modified 1 pulley 2 Wedge 3 inclined plane 4 wheel

Chemistry

1 answer:

valentinak56 [21]2 years ago

8 0

Answer: The answer would be D.

Explanation: When a screw is tightened into an object, it is wedge in between.

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I need help with stoichometrey

alukav5142 [94]

I can help you! What is your question?

8 0

3 years ago

A weak bond called a ______ bond results from an attraction between a slightly positive region in a molecule and a slightly nega

tamaranim1 [39]

Answer: The weak bond having slightly positive region and a slightly negative region is polar covalent bond.

Explanation:

Covalent bond is defined as the bond which is formed by the sharing of electrons between the atoms. For Example: HCl, $CH_4$ etc..

They are of two types:

Polar covalent bond: This bond is formed when difference in electronegativity between the atoms is present. When atoms of different elements combine, it results in the formation of polar covalent bond.

In this bond, a dipole is created. More electropnegative atom will have a slight negative charge and less electronegative atom will have a slight positive charge. For Example: $CO_2,NO_2$ etc..

Non-polar covalent bond: This bond is formed when there is no difference in electronegativity between the atoms. When atoms of the same element combine, it results in the formation of non-polar covalent bond. For Example: $N_2,O_2$ etc..

Hence, the weak bond having slightly positive region and a slightly negative region is polar covalent bond.

7 0

3 years ago

Calcium carbonate is often used as an antacid. Your stomach acid is composed of HCl at a pH of 1.5. If you ate toooo much Turkey

stiks02 [169]

Answer: 0.0237 g of calcium carbonate would be required to neutralize the given amount of HCl

Explanation:

pH is defined as the negative logarithm of hydrogen ion concentration present in the solution

$pH=-\log [H^+]$ .....(1)

Given value of pH = 1.5

Putting values in equation 1:

$1.5=-\log[H^+]$

$[H^+]=10^{(-1.5)}=0.0316M$

Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:

$\text{Molarity of solution}=\frac{\text{Number of moles of solute}\times 1000}{\text{Volume of solution (mL)}}$ .....(2)

We are given:

Volume of solution = 15.0 mL

Molarity of HCl = 0.0316 M

Putting values in equation 2:

$0.0316=\frac{\text{Moles of HCl}\times 1000}{15.0}\\\\\text{Moles of HCl}=\frac{0.0316\times 15.0}{1000}=4.74\times 10^{-4}mol$

The chemical equation for the reaction of HCl and calcium carbonate follows:

$2HCl+CaCO_3\rightarrow H_2CO_3+CaCl_2$

By the stoichiometry of the reaction:

2 moles of HCl reacts with 1 mole of calcium carbonate

So, $4.74\times 10^{-4}mol$ of HCl will react with = $\frac{1}{2}\times 4.74\times 10^{-4}=2.37\times 10^{-4}mol$ of calcium carbonate

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

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

Moles of calcium carbonate = $2.37\times 10^{-4}mol$

Molar mass of calcium carbonate = 100.01 g/mol

Putting values in the above equation:

$\text{Mass of }CaCO_3=(2.37\times 10^{-4}mol)\times 100.01g/mol\\\\\text{Mass of }CaCO_3=0.0237g$

Hence, 0.0237 g of calcium carbonate would be required to neutralize the given amount of HCl

7 0

2 years ago

A car with a mass of 1,100 kg is moving with a velocity of 30 m/s due east . What is the moment?

dexar [7]

Momentum = (mass) x (velocity) = (1,100) x (30) =

33,000

kg-m/sec due east

6 0

2 years ago

(e) Another student investigated the rate of a different reaction

vodka [1.7K]

Answer:

0.07 g/s.

Explanation:

From the question given above, the following data were obtained:

Mass lost = 9.85 g

Time taken = 2 min 30 s

Mean rate =?

Next, we shall convert 2 min 30 s to seconds (s). This can be obtained as follow:

1 min = 60 s

Thus,

2 min = 2 × 60 = 120 s

Therefore,

2 min 30 s = 120 s + 30 s = 150 s

Finally, we shall determine the mean rate of the reaction. This can be obtained as illustrated below:

Mass lost = 9.85 g

Time taken = 150 s

Mean rate =?

Mean rate = mass lost / time taken

Mean rate = 9.85 / 150

Mean rate = 0.07 g/s

Therefore, the mean rate of the reaction is 0.07 g/s

4 0

3 years ago

A screw is an example of a modified 1 pulley 2 Wedge 3 inclined plane 4 wheel​

A screw is an example of a modified 1 pulley 2 Wedge 3 inclined plane 4 wheel