Tag: matter around us

Questions Related to matter around us

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

Electron Volt is a unit of:

  1. Potential difference

  2. Energy

  3. Charge

  4. Velocity

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The electron volt (symbol eV; also written electronvolt) is a unit of energy equal to approximately 1.602$\times$10$^{−19}$ joule (SI unit J). 


By definition, it is the amount of energy gained by the charge of a single electron moved across an electric potential difference of one volt.

Hence, the correct option is $B$

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

The international standards of weight and measures are made of:

  1. gold silver alloys

  2. platinum - iridium alloys

  3. copper - gold alloys

  4. platinum - iron alloys

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The addition of 10% iridium to the platinum greatly increases its hardness and so reduces wear.Hence the international standards of weight and measures are made up of platinum and iridium alloys.
Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

The centigrade $(^0 C)$ scale can be converted into Kelvin scale by the formula:

  1. Temperature in Kelvin + 273

  2. Temperature in Kelvin - 273

  3. Temperature in Fahrenheit + 273

  4. Temperature in Fahrenheit - 273

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The temperature T in Kelvin (K) is equal to the temperature T in degrees Celsius $\displaystyle \left( ^{ \circ  }{ C } \right) + 273$: 


$\displaystyle { T } _{ \left( k \right)  }={ T } _{ \left( ^{ \circ  }{ C } \right)  }+273.15$

Therefore, temperature in $\displaystyle ^{ \circ  }{ C }$ =  temperature in Kelvin +273.

Hence, option B is correct.

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

Convert $-679^{\circ}$ F to celsius.

  1. 412.24

  2. $-$395
  3. 963

  4. $-$400
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

We know,    $\boxed { {  }^{ 0 }C=\left( {  }^{ 0 }F-32 \right) \times \frac { 5 }{ 9 }  } $

                   $\swarrow $               $\searrow $
temp in ${  }^{ 0 }C$                       temp in $F$.
${  }^{ 0 }C=\left( -679-32 \right) \times \dfrac { 5 }{ 9 } $
${  }^{ 0 }C=-395$
$\therefore $  temperature in ${  }^{ 0 }C$  u $-{ 395 }^{ 0 }C$.

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

What is the temperature of water in kelvin if the water is at $44^{\circ}C$ ?

  1. 330

  2. 317

  3. 229

  4. 230

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Temperature in$ K$ = Temperature in $^{\circ}C + 273$


                                     = $44^{\circ}C + 273$

                                    = $317 K$.

So, the correct option is $B$