Answer:
Indicators show changes in the pH of a solution
Explanation:
A pH meter is an instrument that measures the hydrogen-ion activity in aqueous solutions, indicating the acidity or alkalinity of the solution expressed as pH .The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode, hence the pH meter is sometimes referred to as a potentiometric pH meter. Potentiometric pH meters measure the voltage between two electrodes and display the result converted into the corresponding pH value. The instrument comprises of a simple electronic amplifier and a pair of electrodes, or alternatively a combination electrode, and some form of display calibrated in pH units. It usually has a glass electrode and a reference electrode, or a combination electrode. The electrodes, or probes, are inserted into the solution to be tested.
Organic indicators are chemical species that change their colour in response to changes in the pH of the solution. This implies that the anionic and protonated forms of the indicator possess different colours. Hence the colour changes in acidic, basic and neutral solutions. The images attached indicate the colour changes in phenolphthalein and methyl orange in acidic and basic media accordingly.
Answer:
A
Explanation:
With chemical reactions, there are various factors that affect the rate of the reaction. One of these is temperature.
When you raise the temperature, the reaction will move faster. Why? Temperature is directly correlated with the kinetic energy (basically, the energy that makes the particles move). Higher temperatures mean higher kinetic energies. Particles with higher kinetic energies move faster, which makes them more likely to collide. When collisions occur more frequently, the reaction follows through more quickly.
Thus, when Julissa warms the solutions, she will see that bubbling and white solid formation (the products of the reaction) occus faster. So, the answer is A.
Hope this helps!
Answer:
Pupa Stage
Explanation:
Silk worm consists of four stages- the adult, the egg, the larva (caterpillar) and the pupa stage.
Answer:
0.690 g/mL
Explanation:
Density is the ratio of mass to volume:
gasoline mass = (flask+gas mass) - (flask mass) = 145.028 g -110.525 g
gasoline mass = 34.503 g
Density = (gas mass)/(gas volume) = (34.503 g)/(50.0 mL)
Density = 0.690 g/mL
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The least-precise number in this calculation is the sample volume, which has 3 significant figures. Thus, the answer is good only to 3 significant figures.