Sodium reacts with water to produce sodium hydroxide and hydrogen gas:

Two isotopes of hydrogen fuse to form a neutron plus the larger element,A) beryllium.B) carbon.C) deuterium.D) helium.

Nezavi [6.7K]

Answer: D) helium.

Explanation:

Nuclear fission is a process which involves the conversion of a heavier nuclei into two or more small and stable nuclei along with the release of energy.

$_{92}^{235}\textrm{U}+_0^1\textrm{n}\rightarrow _{56}^{143}Ba+_{36}^{90}Kr+3_0^1\textrm{n}$

Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.

Example: $_1^2\textrm{H}+_1^3\textrm{H}\rightarrow _2^4\textrm{He}+_0^1\textrm{n}+\text{energy}$

Thus when deuterium and tritium , the two isotopes of hydrogen are fused, a heavier nuclei helium is being formed from two smaller nuclei releasing a neutron.

3 0

3 years ago

Minerals are very useful to us. Which of the following is a false statement? Question options: Pyrite is an ore of gold and is u

lilavasa [31]

Answer:

The false statement is :

Pyrite is an ore of gold and is used in jewelry making.
Cobalt is not used in medicine.

Explanation:

Pyrite is an ore of iron sulfide found on the Earth and in coal, limestone and in many deposits of metallic ores. Due to its luster and pale yellowish color it appears as gold due to which it is also termed as Fool's gold.

It is used in firearms , in production of sulfur dioxide gas, etc.

Cobalt is used as medicine to treat cancer patient. Co-60 is used in treatment of cancer in which gamma rays produced by Co-60 are used to kill tumor cells in a cancer patient.

Where as talc is used in industries like : paper making, food, paints, plastics etc. Quartz is primary material used to prepare glass and cobalt is used as

4 0

3 years ago

5.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the

cupoosta [38]

Answer: Thus ∆H, in kJ/mol, for the dissolution of MgSO₄ is -66.7 kJ

Explanation:

To calculate the entalpy, we use the equation:

$q=mc\Delta T$

where,

q = heat absorbed by water = ?

m = mass of water = ${\text {volume of water}}\times {\text {density of water}}=100.0ml\times 1.00g/ml=100.0g$

c = heat capacity of water = 4.186 J/g°C

$\Delta T$ = change in temperature = $6.70^0C$

$q=100.0g\times 4.184J/g^0C\times 6.70^0C=2803.3J=2.8033kJ$

Sign convention of heat:

When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

The heat absorbed by water will be equal to heat released by $MgSO_4$

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass = 5.11 g

Molar mass = 120 g/mol

Putting values in above equation, we get:

$\text{Moles of }MgSO_4=\frac{5.11g}{120g/mol}=0.042mol$

0.042 moles of $MgSO_4$ releases = 2.8033 kJ

1 mole of $MgSO_4$ releases = $\frac{2.8033 kJ}{0.042}\times 1=66.7kJ$

Thus ∆H, in kJ/mol, for the dissolution of MgSO₄ is -66.7 kJ

3 0

3 years ago

The temperature of a 500 ml sample of gas increases from 150 k to 300 k. what is the final volume of the sample of gas, if the p

seropon [69]

Upon a constant pressure (P), volume (V) of a gas will vary in direct proportion to changes in temperature (T). So V1/T1 = V2/T2
V2 = V1T2/T1 = (500)(300)/150
V2 = 150000/150 = 1000 mL

5 0

3 years ago

A gas has a pressure of 610.0 mm hg. what is the pressure in atmospheres answer

Semmy [17]

60mmHg = 1 atm
1 mmHg = 1/760atm 
610mmHg = 610/760 
= .80atm

8 0

3 years ago