Answer:
0.50 mol
Explanation:
The half-life is <em>the time required for the amount of a radioactive isotope to decay to half that amount</em>.
Initially, there are 8.0 moles.
- After 1 half-life, there remain 1/2 × 8.0 mol = 4.0 mol.
- After 2 half-lives, there remain 1/2 × 4.0 mol = 2.0 mol.
- After 3 half-lives, there remain 1/2 × 2.0 mol = 1.0 mol.
- After 4 half-lives, there remain 1/2 × 1.0 mol = 0.50 mol.
Answer:
4-Methyl-1-pentene
Explanation:
According to the International Union of Pure and Applied Chemistry (IUPAC), IUPAC nomenclature of organic chemistry is defined as the system of naming organic chemical compounds.
There are certain rules for naming organic chemical compounds as per IUPAC. The name of given (CH3)2CHCH2CH=CH2 will be based on the same rules.
- At first find out the longest continuous chain and number the chain consecutively (preference given to double and single bonds), so numbering will start from right to left. the given chemical is 5 Carbon chain long.
- Then, identify the groups attached to this chain. Methyl is the only group attached to this chain at 4 Carbon.
- Assemble the name in alphabetical order using the full name using correct prefix and suffix.
4-Methyl-1-pentene is the name of this chemical, as methyl is in 4th carbon position, Pent for 5 carbon chain and -ene (suffix) for one double bond).
Hence, the correct answer is "4-Methyl-1-pentene".
Answer:
1.54grams
Explanation:
Molarity of a solution = n/V
Where;
n = number of moles (mol)
V = volume (L)
Based on the information given in this question;
Volume of NaOH solution = 5.0 × 10ml
= 50ml = 50/1000 = 0.050 L
Molarity = 0. 77 M
Using; Molarity = n/V
0.77 = n/0.05
n = 0.77 × 0.05
n = 0.0385mol
To find the mass (grams) of NaOH in the solution, we use the following formula:
mole (n) = mass/molar mass
Molar mass of NaOH = 23 + 1 + 16 = 40g/mol
0.0385 = mass/40
mass = 0.0385 × 40
mass = 1.54grams.
1.regulating ph
2.heating
3.adding some oppositely charged colloids
To find heat, you need the following formula
heat= specific heat x mass x ΔT
specific heat (for water)= 4.184--> according to the table
mass= 100 grams
ΔT= 75 -10= 65 °C
let's plug the values.
specific heat= 4.184 x 100 x 65= 27200 joules or 27.2 Kilojoules
