Which liquid is used in doctor thermometer?

Which liquid is used in doctor thermometer?

In a mercury thermometer, a glass tube is filled with mercury and a standard temperature scale is marked on the tube. With changes in temperature, the mercury expands and contracts, and the temperature can be read from the scale. Mercury thermometers can be used to determine body, liquid, and vapor temperature.

Where should a thermometer be placed in a liquid?

The bulb part of the thermometer is positioned near the side arm of the Y-adaptor so that it monitors the temperature of the vapors. See the illustrations below. If it is too low, it will be too close to the boiling liquid and will read higher than the true vapor temperature.

Which liquid is used in a clinical thermometer and why?

Mercury
Mercury is the only one in liquid state at room temperature. It’s used in thermometers because it has high coefficient of expansion.

Why are clinical thermometers necessary?

A clinical thermometer is used to measure human body temperature. A thermometric liquid is present within the tube which expands proportionally to temperature,hence measures it.

Why thermometer is kept under tongue?

Blood flow is maximum here and the internal body heat is present under the tongue because of which it is placed under the tongue to read the inner body heat. This way we can measure the temperature of the whole body.

Why is the thermometer bulb not immersed in the liquid mixture?

Record the Temperature and Pressure The thermometer bulb must be fully immersed in vapors to register an accurate temperature (Figure 5.27d). Therefore, the temperature near the very beginning and end of the distillation tends to be inaccurate.

What is the purpose of the not touching the tip of the thermometer in any part of the beaker?

a) It’s important to not touch the sides of the test tube with the thermometer because touching it to the sides of the test tube fractures the glass and does not allow for correct temperature measurements.

Why is water not used in thermometer?

Water is not able to be used as a thermometer liquid because of its higher freezing point and lower boiling point than the other liquids in general. This range is very negligible as compared to other liquids like mercury which has a freezing point of about −39∘C and boiling point 356∘C.

Why are airplane thermometers not allowed?

The glass of a mercury thermometer can break. The released mercury can corrode the aluminium of the plane. Such lamps become extremely hot, leading to a fire on the plane. The list of ordinary products posing a hazard in air travel goes on and on.

Is temperature of all body parts of a patient same or different?

Answer: The temperature is different at different body parts. Different body parts have different temperatures and this is evident when a person gets fever. Tongue is always at least 2 degree cooler than armpit. Again, during winters we see that the tip of our nose gets colder while other parts remain warm.

Why do doctors dip the thermometer in alcohol before use?

There are two reasons why the doctor dips in alcohol before use. The first is that any infections of the previous patient may have does not infect others. The second is that the Mercury level should fall down to below 35 degrees centigrade before use. Q: Why doctor dips the thermometer in a liquid before use?

How do you test a thermometer with tap water?

Take some tap water in a beaker or a mug. Dip the thermometer in water so that the bulb is immersed in water but does not touch the bottom or the sides of the container. Hold the thermometer vertically (Fig. 5). Observe the movement of mercury in the thermometer. Wait till the mercury thread becomes steady.

How to use a thermometer?

The thermometer that measures our body temperature is called a clinical thermometer. Hold the thermometer in your hand and examine it carefully. If you do not have a thermometer, request a friend to share it with you. A clinical thermometer looks like the one shown in Fig. 2.

What does a clinical thermometer look like?

A clinical thermometer consists of a long, narrow, uniform glass tube. It has a bulb at one end. This bulb contains mercury. Outside the bulb, a small shining thread of mercury can be seen. If you do not see the mercury thread, rotate the thermometer a bit till you see it. You will also find a scale on the thermometer.