A substance that changes color when placed in an acidic or basic solution is called a

The answer is dnaA, it is a protein that enacts start of DNA replication in microscopic organisms. It is a replication start figure which advances the loosening up of DNA at oriC. The onset of the start period of DNA replication is controlled by the grouping of DnaA.

7 0

3 years ago

Directions: Answer the following questions in complete sentences. a. Describe four properties of acids that you learned in this

sladkih [1.3K]

Answer:

see below

Explanation:

a. Describe four properties of acids that you learned in this lesson.

1. Acids taste sour

For instance, taste some lemon juice

2. Acids are corrosive

Acids in contact with organic tissue or metals attack and, eventually, can destroy them. For instance chloric adis and sulfuric acid. Acids burn the skin.

3. Acids react with metals releasing hydrogen gas

For instance:

$2HCl(aq)+2Na(s)\rightarrow 2NaCl(aq)+H_2(g)\uparrow$

4. The pH of acids is below 7.

pH is the negative logarithm of the hydrodium concentration. HIgh concentrations of hydronum yield low pH: For instance:

$[H_3O]=2.0M \impliespH=-log\dfrac{1}{[H_3O^+]}=-log\dfrac{1}{2}=0.3$

5. Acids conduct electricity:

Acids ionize in water, producing hydronium ions. The ions carry charge. The motion or flow of charge is electric current.

b. Describe four of the properties of bases that you learned in this lesson.

1. Bases taste bitter

For instance, taste some soap

2. Bases are caustic and corrosive

Bases also damage organic tissue and attack metals. Thus they are corrosive such as acids. But strong bases are also named caustic. They cause damage similar to burns but in a different way.

3. The pH of bases is above 7.

pOH is the negative logarithm of OH⁻ ion. And pH + pOH = 14

$[OH^-]=1.0\impliespOH=-log(1/1.0)=-log(0.1)=1\\ \\ pH=14-pOH\\\\pH=13$

4. Bases conduct electricty.

Bases ionize in water releasing OH⁻ which carry charge, the flow of charge is current.

c. What are the products produced when an acid and base react together?

Acids and bases react together neutralizing each other, producing salt and water.

For instance:

$HCl+NaOH\rightarrow NaCl(salt)+H_2O(water)\\\\\\HNO_3+NaOH\rightarrow NaNO_3(salt)+H_2O(water)$

d. Examples of acids and bases. Be sure to check in your fridge, medicine cabinet, and in the cleaning supplies.

From fridge (or the food pantry):

Tomato juice: acid
Lemon juice: acid
Orange juice: acid

soda beverages: acid
vinegard: acid

baking soda: base

From medicine cabinet:

aspirin: acid
ibuprofen: acid

Cleaning supplies:

muriatic acid: acid
soap: base
bleach: base
household ammonia: base
lye: base

e. Names or formulas of acids and bases they may contain.

Tomato juice, lemon juice, and orange juice contain citric acid: C₆H₈O₇

Baking soda is sodium bicarbonate: NaHCO₃

Vinegar is diluted acetic acid: CH₃COOH

Soda beverages: contain carbon dioxide CO₂, and some may contain phosphoric acid H₃PO₄

Muriatic acid is diluted hydrochloric acid: HCl

aspiring is actyilsalicylic acid: C₉H8O₄

ibufrofen is isobutylphenylpropionic acid.

soap: chemically they are fatty acids metal salts.

bleach is sodium hypochlorite: ClOH.

Lye is sodium hyroxide: NaOH

Hosehold ammonia: NH₄OH

f. Find at least five acids and five bases for your list, making sure that there are some items on your list that were not mentioned in the lesson. Whenever possible, list the product/item and the formula or name of the acid or base.

Acids:

citric acid: C₆H₈O₇

soda beverages: carbon dioxide, CO₂
vinegard: acetic acid: CH₃COOH
aspirin: acetylsalicylic acid
ibuprofen: isobutylphenylpropionic acid
muriatic acid: HCl

Bases:

baking soda: sodium bicarbonate: NaHCO₃
soap: fatty acid metal salts.

bleach: sodium hypochlorite: HClO
household ammonia: NH₄OH
lye: sodium hydroxide: NaOH

7 0

4 years ago

For which of these processes is the value of ΔH expected to be negative?I. The temperature (of water) increases when calcium chl

Marina CMI [18]

Answer: B.) I, II, and III

Explanation:

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and $\Delta H$ for the reaction comes out to be negative.

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and $\Delta H$ for the reaction comes out to be positive.

I) The temperature (of water) increases when calcium chloride dissolves in water : Thus the reaction is exothermic and $\Delta H$ for the reaction comes out to be negative.

II) Steam condenses to liquid water : The energy is released when bonds are formed when it coverts from gas to liquid and thus $\Delta H$ for the reaction comes out to be negative.

III) Water freezes : The energy is released when bonds are formed to get converted from liquid to solid and thus $\Delta H$ for the reaction comes out to be negative.

IV) Dry ice sublimes : The energy is absorbed when bonds are broken to get converted from solid to gas and thus $\Delta H$ for the reaction comes out to be positive.

6 0

4 years ago