Redshift is said to be experienced when the light or any other electromagnetic radiations from an object undergo an increase in the wavelength but it does not mean that the light literally becomes red.
Redshift occurs due to the expansion of space. It means the farther away the galaxy is from us, the more space it has expanded in the time.
Because as the light left the galaxy, more of the light has been stretched and so more redshifted the light is.
Five indicators of a chemical change are color change, temperature change, precipitate formation, gas bubble formation and smell or taste change. Since some chemical products are poisonous, detecting a chemical reaction via smell or taste change is not recommended.
Answer:
Explanation:
A mixture of a weak acid and its conjugate base (or a mixture of a weak base and its conjugate acid) is called a buffer solution, or a buffer. Buffer solutions resist a change in pH when small amounts of a strong acid or a strong base are added (Figure 1). A solution of acetic acid and sodium acetate (CH3COOH + CH3COONa) is an example of a buffer that consists of a weak acid and its salt. An example of a buffer that consists of a weak base and its salt is a solution of ammonia and ammonium chloride (NH3(aq) + NH4Cl(aq)).
That is a true statement but you have to ask your teachet
The required is the amount of Sr(OH)2·8H2O needed to prepare a solution having a concentration of 0.100 M OH-. We start with the concentration of the hydroxide ion to determine the number of moles hydroxide ion for a given volume of 250.0 mL solution.
0.100 mol/L (0.250 L) = 0.4 mol hydroxide ion needed.
We know that, for every mole of Sr(OH)2·<span>8H2O in solution, two hydroxide ions is formed. Thus,
0.4 mol OH- ( 1 mol </span>Sr(OH)2·<span>8H2O / 2 mol OH-) ( 265.76 g / mol) = 53.152 g
Thus, 53.152 grams of </span>Sr(OH)2·<span>8H2O is needed to make a solution with 0.100 M OH-.</span>
