All categories

3 years ago

Which of the following statements is true?

1 answer:

5 0

The first statement is False... as
For exothermic reaction :
A+B》 C+D + HEAT..(heat is considered as a product)... as for endo.. heat is a reactant.
So tjey can't be of the same energy...

2nd one...based on the
A+B》 C+D+HEAT...For exo reaction... the product have more Heat energy than potential...so its false
Recall...energy can nither be created nor destroyed but converted from one form to another....

The 4th one however is true for heat...the reactants have nore energy than the products..
A+B+HEAT》C+D

You might be interested in

If you use a horizontal force of 32.0 N to slide a 12.5 kg wooden crate across a floor at a constant velocity, what is the coeff

sergejj [24]

Answer:

Value of coefficient of kinetic friction is 0.26 .

Explanation:

Given:

Mass of wooden crate, m = 12.5 kg.

Horizontal force to keep the block moving with constant velocity, F = 32.0 N.

Since, the block is moving with constant velocity.

So, net force experience by it is zero.

Therefore, fore of friction is equal to applied force.

Now, force of friction , $F=\mu_kN$ ( here $\mu_k$ is coefficient of kinetic friction and N is normal force)

Therefore, $\mu_kN=\mu_k\times mg=\mu_k\times 12.5 \times 9.8=122.5\times \mu_k$

Now, both forces are equal.

$122.5\times \mu_k=32\\\mu_k=\dfrac{32}{122.5}=0.26$

The value of coefficient of kinetic friction is 0.26 .

Hence, it is the required solution.

6 0

3 years ago

QUICK PLEASE

Trava [24]

Answer: 2.52 M

Explanation:

The product of molarity (moles/litre) and volume in litres yields moles, and the numbers of moles in two solutions means dilute and concentrated are equal, which is expressed by the following equation:

$M_1V_1=M_2V_2$

$$Given that\\M $1=12.0 \mathrm{M}$ or mole $/ \mathrm{L}$\\$\mathrm{V} 1=420 \mathrm{ml}$\\$\mathrm{M} 2=$ ?\\$\mathrm{V} 2=2.0 \mathrm{~L}$ or $2000 \mathrm{ml}$\\\\$\mathrm{M} 1 \mathrm{~V} 1=\mathrm{M} 2 \mathrm{~V} 2$\\$\mathrm{M} 2=\mathrm{M} 1 \mathrm{~V} 1 / \mathrm{V} 2$\\$=12.0 * 420 / 2000$\\$=2.52 \ \mathrm{M}$

3 0

2 years ago

Which of the following statements best compares the wavelengths of the regions of the electromagnetic spectrum? O Microwaves are

scZoUnD [109]

Answer:

infrared waves are longer than gamma rays

Explanation:

according to the order :

radio, microwaves, infrared, light, ultraviolet, X-ray, gamma rays

radio waves have the highest wavelenght and lowest frequency, gamma rays have the highest frequency and lowest wavelength.

5 0

3 years ago

How do you figure out molality

hodyreva [135]

*The molality of a solution is calculated by taking the moles of solute and dividing by
the kilograms of solvent* Basically if we had 1.00 mole of sucrose (it's about 342 3 grams) and
proceeded to mix it into exactly 1.00 liter water. It would dissolve and make sugar
water. We keep adding water, dissolving and stirring until all the solid was gone. We
then made sure everything was well-mixed.
What would be the molality of this solution? Notice that my one liter of water weighs
1000 grams (density of water = 1.00 g / mL and 1000 mL of water in a liter).

3 0

2 years ago

Sam investigates the reactivity of metals in air. His observations are shown below.

viva [34]

Answer:5

Explanation:

6 0

3 years ago

Read 2 more answers