Clamps fastener

Fig. 67 The three-fingered clamp with clamp fastener.

Clamp the flask (around the neck) a few inches up the ringstand (Fig. 68). We are using heating mantles and you ll need the room underneath to drop the mantle in case it gets too hot. That s why the flask is clamped at the neck. Yes. That s where the flask is ALWAYS clamped, no matter what heat source, so it doesn t fall when the mantle comes down. What holds the mantle Extension ring and clamp fastener. 

Now add the condenser. Get another ringstand, extension clamp, and clamp fastener. There. Estimate the angle and height the clamp will be at... 

Do the third ringstand—extension clamp — clamp fastener setup. It s handy to think of the extension clamp and clamp fastener as a single unit. Clamp receiving flask in place. Put vacuum adapter in the flask now. Adjust. There Got it. 

OK, get a ringstand and an extension clamp and a clamp fastener and put them all together. What heat source A Bunsen burner, and you ll need more room than you do with a heating mantle (see Chapter 18, Sources of Heat ). In any case, you don t know where the receiving flask will show up, and then you might have to readjust the entire setup. Yes, you should have read the experiment before so you d know about the heating mantles. 

Get an extension clamp and clamp fastener. Open the jaws of the clamp so they re wider than the outer joint on a vacuum adapter. Set this clamp so that it can accept the outer joint of a vacuum adapter at the angle and height you made a mental note of in step 5. 

Most coils are firmly clamped (but not welded) to supports. Supports should allow expansion but be rigid enough to prevent uncontrolled motion (see Fig. ll-29b). Nuts and bolts should be securely fastened. Reinforcement of the inlet and outlet connections through the tank wall is recommended, since bending stresses due to thermal expansion are usually high at such points. 

To protect clamping system, use dissimilar metals to prevent galling on threaded fasteners... 

Clamping plate Mold plate that matches the mold and is used to fasten the mold to the machine. 

Rope should be kept tightly and eyenly wound on the drums. Sudden, severe stresses are injurious, to a wire rope, and should be reduced tt a- minimum. Experience.has.indicated. that, wear increases. with speed . economy results, from, moderately increasing the load and diminishing the speed. F,xcessive speeds may injure Wire rope-., Cafe should be taken to see that the clamps used to fasten the rope for dead endirtg do not kitik, flatten, or crush the, rope,... 

To minimize evaporation of the solvent and evaporation of the aryl bromide starting materials we attempted two reactions in a sealed system with a rubber septum fastened tightly with a plastic clamp to the neck of the Erlenmeyer flask. 

Unfortunately, glass apparatus needs to be held in place with more than just spit and bailing wire. In fact you would do well to use clamps. Life would be simple if there were just one type of fastener, but that s not the case. 

Reaction of a Metal with Water. 1. Fill a test tube with water up to its edges. Close its mouth with your thumb, invert it in a bath with water and fasten it in this position in the clamp of a stand. Wrap up several pieces of metallic calcium in cheese-cloth and rapidly place the metal under the tube with pincers. Determine what gas is evolved. Write the molecular and electron equations of the reaction. 

Fasten a test tube with bromine in a clamp of the stand and throw a narrow strip of aluminium foil into it. If no reaction begins after a minute, put a beaker with warm water (about 40 °C) under the bottom of the test tube. What happens Write the equation of the reaction. 

Introduce a heated strip of copper foil into a test tube filled with bromine and fastened in a stand clamp. What do you observe Write the equation of the reaction. 

Fasten the tube in an inclined position in a clamp of a stand and heat the layer of ammonium chloride below the stopper. What explains the change in the colour of the litmus paper What law does the rate of gas diffusion observe Which of the gases obtained as a result of the thermal dissociation of ammonium chloride diffuses more rapidly, and how many times Write the equation of thermal dissociation of ammonium chloride. 

Preparation of Amorphous Silicon. Pertorm the experiment in a jume cupboard Mix 1 g of dry quartz sand finely comminuted in an iron mortar with 1.5 g of powdered magnesium. Spill the mixture into a test tube fastened in a clamp of a stand over a sheet of iron or asbestos. First heat the tube over its entire length, and then strongly heat its bottom. What do you observe ... 

Preparation of Amorphous Boron from Boric Acid Anhydride. (Each student performs only one of the experiments for preparing amorphous boron.) Put 2 g of boric acid anhydride into an iron crucible or onto an iron plate and roast it if the boric acid anhydride contains moisture, then when it is heated with magnesium an explosion may occur ). Triturate the boric acid anhydride as rapidly as possible (why ) in 4 mortar, weigh 1 g and mix it with 2 g of a magnesium powder. Place the mixture into a refractory test tube and fasten it in an inclined position in a clamp of a stand in a fume cupboard . First carefully heat the test tube with the mixture with the flame of a burner, and then strongly heat the bottom part of the tube. What do you observe ... 

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