How wold you balance this equation? hcl+ba⇒ bacl2+h2 (a) place a 2 in front of the hcl and a 2 in front of the ba (b) place a 2 in front of the hcl (c) place a 2 in font of the ba (d) it is already balanced

The answer is B. Place a 2 in front of the HCl

Ba + 2HCl → BaCl2 + H2

Explanation:

According to the law of the conservation of matter, no atom can create or destroy in a chemical reaction. Then the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products. Therefore, if the number of atoms is not equal, the equation must be balanced.

First you must determine the amount of atoms of each element present in both reagents and products. For that you must observe the subscripts next to each atom. In this case:

Reagents (left side of the reaction):

Products (right side of the equation):

You can see that there aren't the same number of atoms of Cl and H in reagents and products. So you have to balance the chemical reaction.

In a chemical equation, you can change coefficients, but you should never alter the subscripts. And it is always preferable not to start balancing with H. In this case, you start balancing the chlorine. For that you add the coefficient 2 to the HCl molecule to the right of the equation to balance it with the 2 Cl atoms to the left of the equation (present in BaCl2). So:

Ba + 2HCl → BaCl2 + H2

Now you must determine the amount of atoms of each element present in both reagents and products again to see if the reaction is balanced or not. Remember that by multiplying the coefficient by the subindice of each atom, you get the amount of that atom.

Reagents (left side of the reaction):

Products (right side of the equation):

You can see that you have the same amount of each atom on each side of the reaction. This means that the reaction is balanced.

So the answer is

Ba + 2HCl → BaCl2 + H2

and you placed a 2 in front of the HCL

part 1: the half-life of the element is 22 years.

part 2: it will take 132.02 year for the sample to decay from 308.0 g to 4.8125 g.

explanation:

part 1: there are two ways to determine the half life time.

first way: the half life time can be determined directly from its definition as it is the time required for the sample to decay to its half concentration.

from the data the initial concentration was 45.0 g and decayed to its half value (22.5 g) in 22.0 years.

second way: the radio active decay is considered first order reaction so we can use the laws of first order reactions.

k = (1/t) ln (a/a-x), where k is the rate constant of the reaction,

t is the time of the reaction

a is the initial concentration of the reactant

a-x is the remaining concentration at time (t)

a = 45.0 g the initial concentration at t = 0 year.

at t = 22 year, a-x = 22.5 g

then k = (1/22 year) ln (45.0 g/ 22.5 g) = 0.0315 year-1.

the half-life time (t1/2) = ln 2/ k = 0.693/ k =0.693/ 0.0315 = 22 years.

part 2:

using the same law k = (1/t) ln (a/a-x),

using the given data; a = 308.0 g and a-x = 4.8125 g and the calculated k from the part 1 (k = 0.0315 year-1)

t = (1/k) ln (a/a-x) = (1/0.0315) ln (308.0/ 4.8125) = 132.02 years

chemical digestion occurs in the stomach were hcl and pepsin forms chyme, the mouth in which salivary amylase breaks down starch to form bolus, and the small intestine specifically the duodenum.