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4 years ago

Which statement is true?

2 answers:

8 0

The first statement is true because speed, being a scalar quantity, is the rate at which an object covers distance. The average speed is the distance (a scalar quantity) per time ratio. Speed has nothing to do with direction. On the other hand, velocity is a vector quantity because direction is needed for this.

Romashka-Z-Leto [24]4 years ago

8 0

Answer : The correct option is, Speed is a scalar quantity and velocity is a vector quantity.

Explanation :

Speed : It is defined as the distance traveled by the object per unit time.

It is a scalar quantity because it does not depends on the direction of an object but it depends on the magnitude of the object. The unit of speed is, meter/second or m/s.

For example : The speed is written as, 44 m/s.

Velocity : It is defined a the displacement of an object with respect to the time.

It is a vector quantity because it depends on both direction and as well as on magnitude of the object. The unit of velocity is, meter/second or m/s.

For example : The velocity is written as, 44 m/s north.

Hence, the correct option is, Speed is a scalar quantity and velocity is a vector quantity.

You might be interested in

Crystallization from cooling magma describes one way that _____.

puteri [66]

I think the correct answer would be minerals form. Crystallization is the process of forming crystals from solutions and is one way that minerals are formed in the nature. It is a solid-liquid type of separation. Hope this answers the question. Have a nice day.

3 0

4 years ago

Read 2 more answers

Mercury(II) oxide (HgO) decomposes to form mercury (Hg) and oxygen (O2). The balanced chemical equation is shown below.

zavuch27 [327]

15.63 mol. You need 15.63 mol HgO to produce 250.0 g O_2.

Step 1. Convert grams of O_2 to moles of O_2

Moles of O_2 = 250.0 g O_2 × (1 mol O_2/32.00 g O_2) = 7.8125 mol O_2

Step 2. Use the molar ratio of HgO:O_2 to convert moles of O_2 to moles of HgO

Moles of HgO = 0.8885 mol O_2 × (2 mol HgO/1 mol O_2) = 15.63 mol HgO

7 0

4 years ago

Read 2 more answers

9. How many grams are in 2.0 x 105 molecules of carbon monoxide?

timama [110]

Answer: 9.3 x 10^ 18 g CO

Explanation:

Start by knowing that carbon monoxide is the compound CO. To convert molecules to grams, you first need to convert molecules to moles. This can be done using the conversion factor for Avogadro's Number:

(2.0 x 10^5 molecules CO) x 1 mol CO / 6.02 x 10^23 molecules CO

This cancels molecules CO.

Then, you can convert moles to grams, which is your desired quantity. You can find the number of grams for CO by looking at the periodic table and adding together their masses. C = 12 g and O = 16 g. Total of 28 g CO:

(1 mol CO) x 28 g CO / 1 mol CO

This cancels mol CO, which leaves grams CO.

5 0

3 years ago

A gaseous mixture composed of 20% CH4, 30% C2H4, 35% C2H2, and 15% C2H20. What is the average molecular weight of the mixture? a

Semenov [28]

Answer: The correct answer is Option d.

Explanation:

We are given:

Mass percentage of $CH_4$ = 20 %

So, mole fraction of $CH_4$ = 0.2

Mass percentage of $C_2H_4$ = 30 %

So, mole fraction of $C_2H_4$ = 0.3

Mass percentage of $C_2H_2$ = 35 %

So, mole fraction of $C_2H_2$ = 0.35

Mass percentage of $C_2H_2O$ = 15 %

So, mole fraction of $C_2H_2O$ = 0.15

We know that:

Molar mass of $CH_4$ = 16 g/mol

Molar mass of $C_2H_4$ = 28 g/mol

Molar mass of $C_2H_2$ = 26 g/mol

Molar mass of $C_2H_2O$ = 48 g/mol

To calculate the average molecular mass of the mixture, we use the equation:

$\text{Average molecular weight of mixture}=\frac{_{i=1}^n\sum{\chi_im_i}}{n_i}$

where,

$\chi_i$ = mole fractions of i-th species

$m_i$ = molar masses of i-th species

$n_i$ = number of observations

Putting values in above equation:

$\text{Average molecular weight}=\frac{(\chi_{CH_4}\times M_{CH_4})+(\chi_{C_2H_4}\times M_{C_2H_4})+(\chi_{C_2H_2}\times M_{C_2H_2})+(\chi_{C_2H_2O}\times M_{C_2H_2O})}{4}$

$\text{Average molecular weight of mixture}=\frac{(0.20\times 16)+(0.30\times 28)+(0.35\times 26)+(0.15\times 42)}{4}\\\\\text{Average molecular weight of mixture}=6.75$

Hence, the correct answer is Option d.

3 0

3 years ago

The turnover number is defined as the maximum number of substrate molecules that can be converted into product molecules per uni

Nataliya [291]

Answer:

Explanation:

turn over number = R max / [E]t = K2

From given , R max = 249 * 10 ^ -6 mol. L^-1

T [E]t = 2.23 n mol. L^-1

= 2.23 * 10^-9 mol. L^-1

Putting values in above equation,

= 111.65 * 10^3 S^-1

Turn over number is maximum no of substrate molecule that can be converted into product molecules for unit time by enzyme molecule.

5 0

3 years ago