7-Switch off , remove the beaker and weigh it . 8-Calculate the specific latent heat of fusion of ice . 9-Change a factor and repeat the experiment. 10-Explain the relationship between your chosen variable and the specific latent heat of fusion of ice and comment on your results . Note: The experiment was done at room temperature and not 0 degrees so of course , the result will be different than the one known, which is 300000 j/kg , but as the main point of this experiment is to see if latent heat changes with the change of time , so it won’t affect the experiment .
This means it takes 0.385 Joules of energy to raise one gram of pennies one degree Celsius. Because of its low specific heat, it does not take much energy at all to heat up the coin, which is evident if a penny is picked off of the sidewalk on a hot day. And what if a person were to try to put a coin that they had just found on the hot sidewalk into a vending machine for a drink? In order to be sure that the coin would fit, scientists use a special property called linear thermal expansion to determine how much the coin would expand when heat is applied to it. The purpose of the following experimentation was to use two intensive physical properties, specific heat and linear thermal expansion, to determine if a sample of an unknown metal was Zinc.
No controlled air pollutants, such as sulfur and particulates, or greenhouse gases will be produced by nuclear power plants. The use of nuclear energy will definitely helps to keep the air clean, preserve the earth's climate, avoid ground-level ozone formation and prevent acid rain. Compared to all other energy, nuclear offers the lowest effect on the environment including water, land, habitat, species, and air resources. Nuclear energy is the most eco-efficient of all energy sources because it produces the most electricity relative to its environmental impact. Along with other sustainable energy sources, nuclear power is a low carbon power generation method of producing electricity, with an analysis of the literature on its total life cycle emission intensity finding that it is similar to other renewable sources in a comparison of greenhouse gas(GHG) emissions per unit of energy generated.
A colorless, odorless liquid that freezes at 0°C is probably water, for example. The chemical properties of a substance are those properties that can only be observed when the substance is undergoing a change in composition. The fact that hydrogen peroxide decomposes to give oxygen gas and water is an example of a chemical property. In a physical change, only the temperature, size, or physical state of a sample of matter is altered. The melting of ice and the evaporation of gasoline are examples of physical changes.
Colligative properties can be described reasonably well by a simple equation for solutions of non-electrolytes. The “abnormal” colligative properties of electrolyte solutions supported the Arrhenius theory of ionization. Deviations from ideal behavior for electrolyte solutions led to the determination of activity coefficients and the development of the theory of interionic attractions. The equation for the freezing point depression of a solution of a non-electrolyte as a function of molality is a very simple one (as you may remember from GEN CHEM): Δ TF = K F m (1) The constant KF, the freezing point depression constant, is a property only of the solvent, as given by the following equation, whose derivation is available in many physical chemistry texts1: ( ) o 2 MW(Solvent)R TF KF = 1000 Δ H F (2) In equation (2), R is the gas constant in J/K*mol, TFo is the freezing point of the solvent (K), ΔHF is the heat of fusion of the solvent in J/mol, and the factor of 1000 is needed to convert from g to kg of water for molality. For water, KF = 1.860 o/molal from the
According to the laws of physics, what we consider cold is in reality the absence of heat. Everybody or object is susceptible to study when it has or transmits energy, and heat is what makes a body or matter have or transmit energy. Absolute zero (-460 degrees F) is the total absence of heat; all matter becomes inert and incapable of reaction at that temperature. Cold does not exist. We have created this word to describe how we feel if we have no heat” (Einstein).
- signs of chemical change = changes the shape and color, creates a gas, distributes heat, Etc. - Chemical Change= Substance is formed into a completely new substance 2. Hypothesis: If the copper is being tested in these metals ( Copper, Magnesium and cupric chloride) then it would be the least reactive out of magnesium and zinc because it is the lowest among the three on the activity series. 3. Experimental Design: - Independent Variable: different types of metals: magnesium, zinc and Copper - Dependent Variable: amount of reactants observed for each metal - Control : The Air -Constants: The amount of chemical solutions, the time the metals were in the chemical solutions and size of each metal during the experiment 4.
By applying Hess’s law to the first two reactions, you will be able to calculate the enthalpy change for the third reaction and compare it to the value you obtained experimentally. Heat cannot be measured directly (like mass on a balance or volume in a graduated cylinder), but only through indirect methods such as finding the temperature change it creates in a known material. For a pure substance, the temperature change is a function of the specific heat of the material (c), it mass (m) and the amount of heat absorbed or lost (q): q=m•c•T (for pure substances) Specific heat is an intensive property and is only defined for a homogeneous material. For heterogeneous mixtures, the more general extensive property of heat capacity (C) is used: q= C•T (for
Nuclear fission produces no greenhouse emissions (Alexander 1). This is also good for our atmosphere (Alexander 1). As nuclear energy is produced, there are no sulfur dioxide or nitrogen oxides being produced with it, unlike the burning of fossil fuels (Rastogi 1). These oxides can cause acid rain which is very bad for the environment